Freeze the centers: Line a plate with parchment. Scoop 10 to 12 small mounds (about 2 teaspoons each) of Biscoff cookie butter. Freeze for 30 to 45 minutes until firm.
Prep the dry mix: In a bowl, whisk flour, baking soda, baking powder, salt, and cinnamon.
Mix the wet: In a large bowl, whisk melted butter, brown sugar, and granulated sugar until glossy and combined.
Add the egg and vanilla; whisk until smooth.
Combine: Add dry ingredients to wet and fold until just combined. Stir in crushed Biscoff cookies. The dough will be soft but not sticky.
Chill for 20 to 30 minutes if very warm.
Preheat: Heat oven to 350°F (175°C). Line two baking sheets with parchment.
Shape: Scoop dough into 2-tablespoon portions. Flatten each into a disk, place a frozen Biscoff center in the middle, and wrap the dough around it, sealing well.
Place seam-side down on the sheet, spaced 2 inches apart.
Bake: Bake 9 to 11 minutes until edges are set and lightly golden but centers look soft and slightly underdone.
Finish: While hot, gently “scoot” cookies with a round cutter or spoon to make perfect circles. Sprinkle with extra crushed Biscoff, or drizzle warm cookie butter on top. Cool 5 to 10 minutes before serving for maximum lava.