Prepare Pan: Line 8×8 dish with parchment paper.
Melt Base: Combine chocolate chips, condensed milk, and butter over low heat until smooth.
Flavor It: Stir in vanilla extract.
Pour and Smooth: Spread mixture into pan evenly.
Swirl the Jam: Warm jam, tint red, drizzle and swirl lightly with knife.
Chill: Refrigerate for 2 hours or overnight.
Serve: Cut into squares, wipe knife between slices for clean edges.
