Add the sugar to a small saucepan and cook over medium to medium-high heat, whisking constantly until it melts into a deep amber caramel.

Stir in the butter until fully melted and smooth, then reduce the heat slightly. Pour in the heavy cream little by little, mixing well until the caramel is glossy and combined.

Remove from the heat and let it cool completely until slightly thickened.

In a medium bowl, whisk together the sweetened condensed milk, vanilla, half-and-half, and half of the cooled caramel until smooth.

In a separate bowl, beat the heavy cream with a hand mixer or stand mixer until stiff peaks form.

Gently fold the whipped cream into the caramel-condensed milk mixture to make a smooth no-churn ice cream base.

Fold in the chopped peanuts so they are evenly spread throughout.

Spoon in the remaining caramel a little at a time and lightly swirl it through the mixture with a knife or fork. Do not overmix, so the caramel stays in ribbons.

Transfer the mixture into ice cream bar molds, insert wooden sticks, and freeze uncovered for 3 to 5 hours, or until fully firm.

You can also use a parchment-lined 9 x 13-inch baking dish instead of molds.

Remove from the molds and serve immediately. For extra flavor, top with more caramel and chopped peanuts.