Prepare Oven & Pan: Preheat oven to 350°F (175°C). Line a 12-cup muffin tin with cupcake liners.
Mix Dry Ingredients: In a small bowl, whisk flour, baking powder, and salt. Set aside.
Cream Butter & Sugars: In a large bowl, beat softened butter, granulated sugar, and brown sugar until light and fluffy (about 2–3 minutes).
Add Wet Ingredients: Beat in eggs one at a time, then mix in vanilla and peanut butter until smooth.
Combine Batter: Alternate adding dry ingredients and milk, beginning and ending with dry ingredients. Mix gently until just combined.
Fold in Chips: Stir in peanut butter chips until evenly distributed.
Fill & Add Lava Center: Spoon batter into liners, filling each 2/3 full. Press a small spoonful of peanut butter into the center of each cupcake, then cover with more batter.
Bake: Bake 18–22 minutes, until a toothpick inserted near the edge comes out clean (the center should stay gooey).
Finish: Sprinkle chocolate chips on top right after baking for a melty finish, if desired.
Serve: Allow to cool slightly, then enjoy the gooey lava surprise inside!
Serving and Storage Tips
