Creating these Pistachio Chocolate Lava Cakes is simple if you follow these steps:

1. Preheat Oven: Preheat your oven to 425°F (220°C). Grease four ramekins with butter and dust with flour.
2. Melt Chocolate and Butter: In a microwave-safe bowl, combine the butter and semi-sweet chocolate chips. Heat in the microwave in 30-second intervals, stirring until smooth and combined.
3. Whisk Eggs: In a separate bowl, whisk together the eggs, egg yolks, and granulated sugar until pale and fluffy.
4. Combine Mixtures: Gradually add the melted chocolate mixture to the egg mixture, stirring gently until combined.
5. Add Vanilla and Dry Ingredients: Stir in the vanilla extract. Then, gently fold in the flour, salt, and finely chopped pistachios until just combined.
6. Fill Ramekins: Pour the batter evenly into the prepared ramekins, filling each about ¾ full.
7. Bake: Place the ramekins on a baking sheet and bake in the preheated oven for 12-15 minutes, or until the edges are firm but the center is still soft.
8. Cool Slightly: Remove the ramekins from the oven and let them cool for about 5 minutes. This cooling time helps the cakes set slightly while still ensuring a gooey center.
9. Invert and Serve: Carefully run a knife around the edges of the ramekins. Invert each ramekin onto a plate to release the cake.
10. Dust with Powdered Sugar: If desired, dust the tops with powdered sugar for an elegant finishing touch.

By following these straightforward instructions, you’ll have a batch of Pistachio Chocolate Lava Cakes ready to impress.