Preheat your oven to 350°F (175°C) to ensure even baking.
Grease a muffin tin or line it with paper liners to prevent sticking.
In a large mixing bowl, whisk together the all-purpose flour, instant pistachio pudding mix, granulated sugar, brown sugar, baking soda, and sea salt until well combined.
In a separate bowl, mix the vegetable oil, egg, sour cream, milk, vanilla extract, and almond extract. Whisk until smooth and fully combined.
Pour the wet ingredients into the dry ingredients and gently stir with a spatula until just combined; a few lumps are okay.
Fold in the roughly chopped shelled pistachios, distributing them evenly throughout the batter.
Fill each muffin cup about two-thirds full using a spoon or ice cream scoop, allowing room for rising.
Sprinkle coarse sugar and extra chopped pistachios on top of each muffin for a crunchy finish.
Bake in the preheated oven for 18-20 minutes, or until a toothpick inserted in the center comes out clean.
Remove muffins from oven and cool in the tin for a few minutes, then transfer to a wire rack to cool completely before serving.