Add the cacao powder to a small saucepan with 4 tablespoons of water. Heat over medium-low heat and stir continuously, until thick, creamy, and combined.

Add ½ cup of the heavy whipping cream to the saucepan and mix until well-combined.

Pour in the chocolate chips and continue stirring constantly until a thick chocolate ganache forms and everything is well-combined.

Stir in ½ cup of the peanut butter.

Pour the rest of the heavy whipping cream (about 1 ½ cups), the sweetened condensed milk, and the chocolate mixture in a high-powered blender. Blend on a low speed just until everything is creamy and combined. Avoid over-mixing to ensure small ice crystals don’t form during the freezing process. If you don't own a blender, you can perform this step using an electric hand mixer and a large bowl.

Dollop half of the remaining peanut butter on the bottom of a 9” x 5” loaf pan (or freezer-safe container), creating little peanut butter lumps.

Pour the chocolate peanut butter ice cream base into the loaf pan, then dollop the remaining peanut butter on top. If you'd like, you can swirl the peanut butter, creating a peanut butter swirl.

Cover with plastic wrap and freeze for at least 6 hours, or until the ice cream has completely set up.

Note: if you own an ice cream maker, you can churn the peanut butter chocolate ice cream base in your ice cream maker. Make sure to follow the manufacture instructions of your ice cream maker (which typically involves freezing the ice cream bowl for at least 24 hours ahead of time).

When you’re ready to serve the ice cream, bring it out of the freezer and thaw it on the counter for 5 to 10 minutes before scooping and serving.