01 - Preheat oven to 350°F. Line a 12-cup muffin tin with paper liners.
02 - Combine chopped dark chocolate and heavy cream in a microwave-safe bowl. Microwave in 20-second intervals, stirring between each, until smooth. Cool briefly, then form 12 small mounds (approximately 1 tsp each) on a parchment-lined plate. Freeze for minimum 15 minutes until solid.
03 - Sift flour, cocoa powder, baking powder, baking soda, and salt into a medium bowl. Whisk to ensure even distribution.
04 - In a large bowl, whisk melted butter and granulated sugar until fully incorporated. Add eggs one at a time, whisking thoroughly after each addition. Stir in vanilla extract.
05 - Add half of the dry ingredients to the wet mixture, mixing gently. Pour in buttermilk, then add remaining dry ingredients. Fold until just combined—avoid overmixing to prevent tough texture.
06 - Place 1 heaping tablespoon of batter into each liner. Position a frozen chocolate mound in the center, pressing lightly into batter. Add 2–3 raspberries per cupcake, then cover with remaining batter until liners are 3/4 full.
07 - Bake for 14–16 minutes until tops are set but centers retain slight softness. Avoid overbaking to preserve molten center.
08 - Let cupcakes rest in pan for 5 minutes, then transfer to wire rack. Dust with powdered sugar and garnish with fresh raspberries and chocolate shavings if desired. Serve warm for optimal lava effect.