To make the filling: Whisk together the softened cream cheese, powdered sugar, egg yolk, and vanilla until smooth. Divide into 4 sections of an ice cube tray and freeze until solid (at least 2 hours).

Preheat oven to 400°F (200°C). Generously grease four 6-ounce ramekins with butter and dust with flour.

In a medium bowl, whisk melted butter and sugar. Mix in eggs, vanilla, and food coloring.

In a small bowl, sift together flour, cocoa powder, and salt.

Add half the dry ingredients to the wet mixture, folding gently. Stir in buttermilk. Fold in remaining dry ingredients just until combined.

Fill ramekins half full with batter. Place a frozen cream cheese piece in the center of each. Top with remaining batter to cover the filling.

Bake on a baking sheet for 12-14 minutes, until edges are firm but centers still jiggle.

Let cool for 1 minute, then carefully invert onto plates. Top with ice cream, chocolate sauce, and cookie crumbs. Serve immediately.