Preheat oven to 350. Add peanut butter, egg, brown sugar and vanilla together with a spatula until completely combined. Fold in chocolate chunks.
Line a baking pan with parchment paper. Use a small size cookie scooper or teaspoon and place dough on parchment lined cookie sheet (approx 16 cookies for smaller cookies or 12 for larger cookies). Use the back of a fork to score the cookie and flatten them out a bit. You may need to dip the fork in water so it doesn't stick to the cookie dough. cook for 10 minutes, allow to cool completely on a wire rack.
Place cooled cookies in the freeze for 30 mins - 1 hour.
For the Nice Cream
Remove bananas from the freezer and let them sit out on the counter for 10-15 minutes.
Place bananas in the food processor and process until the bananas turn into the same consistency as ice cream. Add vanilla and cacao powder - you can leave out the cacao powder if you desire. Turn food processor back on and mix until incorporated.
For the Nice Cream Sandwiches:
Remove cookies from freezer and line half of the cookies with the bottom of the cookie facing up on a cookie sheet. Place enough of the nice cream on top of the cookie to fill the top about ½-1 inch high. Place another cookie on top to make a sandwich. Work quickly before the nice cream melts. Place sandwiches back in the freezer (keep them on the cookie sheet) until frozen.
Serve immediately from freezer as a "healthier" version of an ice cream sandwich.
Recipe by Good Thyme Kitchen at https://www.goodthymekitchen.com/peanut-butter-chocolate-nice-cream-sandwiches/