Bright, fragrant, and layered with contrasting textures, these Vietnamese Lemongrass Beef and Spaghetti Squash Noodle Bowls with Peanut Sauce are the kind of weeknight meal that tastes like a treat but comes together with approachable steps. Tender skirt steak gets a punch of lemongrass and ginger, quick-sautéed vegetables bring crunch and umami, and roasted spaghetti squash stands in for noodles to keep things light. A rich, slightly spicy peanut sauce ties everything together — creamy coconut milk, peanut butter, brown sugar, and Thai red curry paste create a sauce that’s equal parts savory and comforting. Top with crunchy peanuts, fresh herbs, shredded carrots, and sliced chilies and you’ve got bowls that look restaurant-polished and feel homey at the same time.

This recipe keeps the focus on real, simple ingredients: fresh lemongrass, ginger, garlic and a small handful of pantry staples transform skirt steak into sticky, fragrant beef. Spaghetti squash makes an ideal gluten-free, veggie-forward noodle base, and a quick sauté of bok choy and mushrooms rounds out the bowls. The peanut sauce is ready in minutes and doubles as a drizzle and a dip.

Why you’ll love these bowls

Quick marinated beef: Thinly sliced skirt steak soaks up lemongrass, ginger and garlic for bold flavor in minutes.
Vegetable “noodles”: Spaghetti squash is an easy, low-carb alternative to pasta and bakes while you prep everything else.
Make-ahead friendly: Peanut sauce keeps well and the beef can be marinated ahead for even more depth.
Bright, fresh toppings: Mint, shredded carrots, chopped lemongrass and chilies make each bite vibrant and textural.

Ingredients

2 tablespoons fresh lemongrass, chopped (or 1 tablespoon lemongrass paste)
2 tablespoons fresh ginger, grated
2 tablespoons honey
2 tablespoons soy sauce
1 tablespoon fish sauce (found in the asian aisle of most grocery stores)
2 cloves garlic, minced or grated
1 pound beef skirt steak, sliced thin against the grain
1 medium sized spaghetti squash
3 tablespoons peanut or sesame oil
1 head bok choy, chopped
8 ounces mushrooms, sliced
Chopped peanuts, sliced red chilies, shredded carrots, fresh mint, fresh thai basil, chopped lemongrass, for serving
1 ounce can coconut milk (14, lite or regular)
3/4 cup creamy peanut butter
1/4 cup brown sugar
2 tablespoons soy sauce
2 teaspoons thai red curry paste (use 1 teaspoon for less heat)

Prep tips before you start

Slice the skirt steak thin against the grain for tenderness and quicker cooking.
If using fresh lemongrass, remove tough outer layers and finely chop the pale inner stalk. If using lemongrass paste, use 1 tablespoon instead of 2 tablespoons chopped.
Preheat your oven for the spaghetti squash so it’s ready while you prepare the beef and sauce.

Step-by-step directions

The following directions are rewritten into clear, step-by-step instructions following the ingredient list and preserving amounts. Read through once, then follow each numbered step.

Preheat oven to 400°F (200°C). Line a baking sheet with parchment or lightly oil it.
Prepare the spaghetti squash: cut the 1 medium sized spaghetti squash in half lengthwise, scoop out the seeds, and place the halves cut-side down on the prepared baking sheet. Roast 30–40 minutes, until the squash is tender and the flesh easily shreds into strands with a fork. Remove from oven and set aside to cool slightly. Use a fork to scrape out the strands and transfer them to a bowl; cover to keep warm.
While the squash roasts, make the lemongrass-ginger beef marinade: In a bowl, combine 2 tablespoons fresh lemongrass (chopped) or 1 tablespoon lemongrass paste, 2 tablespoons fresh ginger (grated), 2 tablespoons honey, 2 tablespoons soy sauce, 1 tablespoon fish sauce, and 2 cloves garlic (minced or grated). Stir to combine.
Add 1 pound beef skirt steak, sliced thin against the grain, to the marinade. Toss thoroughly so each slice is coated. Let the beef marinate at room temperature for 10–15 minutes while you prepare the vegetables and peanut sauce. If you prefer a deeper flavor, refrigerate and marinate up to 2 hours; bring back to room temperature before cooking.
Make the peanut sauce: In a small saucepan over low heat, combine 1 ounce can coconut milk, 3/4 cup creamy peanut butter, 1/4 cup brown sugar, 2 tablespoons soy sauce, and 2 teaspoons Thai red curry paste (or 1 teaspoon for less heat). Stir continuously until the mixture is smooth and warmed through, about 3–5 minutes. Taste and adjust: add a splash of water if it’s too thick, or a touch more brown sugar if you prefer sweeter. Remove from heat and cover to keep warm.
Heat a large skillet or wok over medium-high heat. Add 1 tablespoon of the 3 tablespoons peanut or sesame oil to the pan. Working in a single layer and in batches if needed, add the marinated skirt steak slices and sear until browned and cooked through, about 1–2 minutes per side depending on thickness. Transfer the cooked beef to a plate and tent loosely with foil to keep warm.
In the same skillet, add the remaining 2 tablespoons peanut or sesame oil. Add 1 head bok choy (chopped) and 8 ounces mushrooms (sliced). Sauté, stirring occasionally, until the bok choy is wilted and the mushrooms are tender and lightly browned, about 4–6 minutes. If the pan gets too dry, add a splash of water or soy sauce to deglaze and loosen any fond.
Return the cooked beef to the skillet with the vegetables and toss briefly to reheat and marry flavors, about 1 minute. Remove from heat.
To assemble the bowls: Divide the warm spaghetti squash strands among serving bowls. Top each bowl with a portion of the lemongrass beef and sautéed bok choy and mushrooms.
Drizzle each bowl generously with the warm peanut sauce. Garnish with chopped peanuts, sliced red chilies, shredded carrots, fresh mint, fresh Thai basil, and extra chopped lemongrass as desired. Serve immediately.

Serving suggestions and variations

Protein swap: If you prefer another cut, flank steak or sirloin sliced thin against the grain will work similarly; cook to your preferred doneness.
Vegetable add-ins: Bell peppers, snow peas, or thinly sliced cucumbers add freshness and crunch.
Heat control: Start with 1 teaspoon Thai red curry paste if you prefer milder spice and increase to taste.
Make it saucier: Reserve extra peanut sauce to serve on the side for drizzling or dipping.

Make-ahead and storage

Peanut sauce: Store in an airtight container in the refrigerator for up to 5 days. Rewarm gently and thin with a little water or coconut milk if it thickens.
Cooked beef and vegetables: Keep refrigerated in separate containers for up to 3 days. Reheat in a skillet over medium heat with a splash of oil or water.
Spaghetti squash: Store roasted strands in an airtight container for up to 4 days. Reheat in the microwave or toss briefly in a skillet with a little oil to revive texture.

Notes on ingredients

Lemongrass: Fresh lemongrass provides the best flavor. If you use lemongrass paste, use the smaller amount called for in the ingredient list and adjust to taste.
Fish sauce: Adds depth and umami. If you prefer to avoid it, a splash of soy sauce plus a pinch of sea salt can be substituted; keep the stated amount of soy sauce as written in the ingredient list.
Coconut milk can: The ingredient list specifies a 1 ounce can coconut milk (14, lite or regular). Use whichever you have on hand.

Tips for perfect results

Slice beef thin and against the grain to keep each bite tender.
Don’t overcook the mushrooms — brown them so they have concentrated flavor without becoming soggy.
Roast the spaghetti squash cut-side down for juicier strands; bake until fork-tender so the strands separate cleanly.
Warm the peanut sauce just until smooth — overheating can change texture. Add water or coconut milk to adjust consistency.

Final thoughts

These Vietnamese Lemongrass Beef and Spaghetti Squash Noodle Bowls with Peanut Sauce offer a balance of fragrant aromatics, meaty richness, and bright garnishes that make every spoonful satisfying. They’re flexible — scale up for a crowd, prep components ahead for speedy weeknight dinners, or switch up the toppings to suit what you have on hand. Each bite brings the sweet-salty-umami interplay that makes Vietnamese-inspired cooking so craveable, with a creamy, slightly spicy peanut sauce to pull it all together. Enjoy the contrast of tender beef, silky peanut sauce, crisp vegetables, and the satisfying “noodle” texture of spaghetti squash.

Happy cooking — and if you try these bowls, tuck a little extra peanut sauce aside for dipping spring rolls or drizzling over rice the next day.