Freeze 4 plain serving cups for 10 minutes.

Pulse 12 cookies into coarse crumbs in a food processor; break remaining 4 into small chunks.

Blend softened ice cream and milk for 10 seconds until thick and movable.

Fold crumbs and chunks into ice cream with 3 broad strokes, leaving streaks.

Divide among chilled cups; drizzle each with 1 tablespoon fudge sauce. Serve immediately.