Place chicken breasts in a large mixing bowl and pour in buttermilk to fully submerge. Marinate for at least 30 minutes or up to overnight in the refrigerator.
In a shallow dish, combine all-purpose flour, garlic powder, onion powder, paprika, salt, and black pepper. Mix well.
Heat vegetable oil in a skillet or deep frying pan over medium-high heat. Oil should be enough to submerge chicken halfway. Test oil readiness by dropping a small amount of flour; it should sizzle.
Remove chicken from buttermilk, letting excess drip off. Dredge each piece in the seasoned flour mixture, pressing lightly. Shake off excess flour and set aside.
Fry chicken breasts in hot oil for 5-7 minutes on each side until golden brown and cooked through (internal temperature 165°F). Drain on paper towels.
Mix truffle honey and white truffle oil (if using) in a small bowl until combined to make the honey truffle sauce.
Preheat oven to 425°F. Toss trimmed asparagus with olive oil, sea salt, black pepper, garlic powder, and lemon juice on a baking sheet. Roast for 10-15 minutes until tender and slightly crispy.
Plate the crispy chicken breasts, drizzle generously with honey truffle sauce, and serve alongside roasted asparagus.