Mix ground cookies, butter, and 1 tablespoon sugar together in a bowl until combined. Press into the bottom of a 9-inch springform pan. Top crust with 1/4 cup caramel chips and 2 tablespoons chopped peanuts.
Mix cream cheese and 1 1/2 cups sugar together until smooth. Blend in milk. Mix in eggs 1 at a time; stir until just incorporated. Mix in sour cream, vanilla extract, and 2 tablespoons flour, using a wooden spoon, until batter is smooth.
Chop 6 mini candy bars into small pieces; toss with 1 tablespoon flour in a bowl (to prevent sinking to bottom of cake). Stir into batter; pour into crust-lined pan.
Bake in the preheated oven for 1 hour. Keep door closed. Turn off heat; let cake cool in the oven for at least 3 hours. Remove from oven; chill 8 hours to overnight.
Release cake from pan; transfer to a serving plate. Decorate top edge of cake with whipped cream. Put remaining 1/4 cup caramel chips and 2 tablespoons chocolate chips in separate microwave-safe bowls; heat in the microwave until melted, about 1 minute. Drizzle melted caramel over cake; repeat with melted chocolate. Chop remaining candy bars and arrange on top of whipped cream. Sprinkle remaining 2 tablespoons peanuts on cake.