In a mixing bowl, combine the half and half, no-stir peanut butter, sugar, salt, and vanilla. Blend on medium speed until the mixture is completely smooth, about 2-3 minutes. Once blended, cover and chill it in the refrigerator for 2-3 hours to help develop the flavors.

After chilling, pour the mixture into your ice cream maker and churn according to the manufacturer's instructions for about 20-30 minutes until it reaches a soft-serve consistency. Transfer to a container and freeze for 1-2 hours.

Line a 9-inch round baking pan with plastic wrap, ensuring there's enough overhang to cover the top later.

Place the cooled fudgy brownie layer at the bottom of the prepared pan. Drizzle this with hot fudge and salted caramel, then sprinkle with chopped peanuts. Add a layer of peanut butter ice cream, and repeat until all ingredients are used, finishing with a layer of ice cream on top.

Drizzle more hot fudge, salted caramel, and sprinkle additional peanuts on top. Cover the pan tightly with plastic wrap and freeze for at least 4-6 hours or until completely firm.

When ready to serve, remove the cake from the freezer and let it sit at room temperature for 5-10 minutes for easier slicing.