Make the peanut butter chunks: measure 1/2 cup of creamy peanut butter. Drop 1/2 tsp portions of peanut butter onto a baking sheet lined with a silicone baking mat or parchment paper. You should have roughly 48 peanut butter chunks. Place the tray in the freezer until frozen, about 45-60 minutes.
In a mixing bowl combine the sweetened condensed milk and the remaining 1 cup creamy peanut butter with a spatula until smooth. Set aside.
In a stand mixer or using a handheld mixer, beat the heavy whipping cream and vanilla extract until stiff peaks form.
Add in the sweetened condensed milk / peanut butter mixture, beating on low until combined.
Fold in the frozen peanut butter chunks, reserving a dozen for the top of the ice cream.
Transfer the ice cream to a loaf pan, 8 inch cake pan, or similar container. Add the additional peanut butter chunks on top, pressing them in slightly. Cover the pan with plastic wrap or a lid and freeze for at least 6 hours, overnight is preferred.
Notes
Store this Peanut Butter Ice Cream in the freezer for up to 2 weeks. I recommend letting it sit on the counter for 10 minutes before scooping.