To make the ice cream:

1. Peel bananas and slice crosswise into coins. Place in a single layer on parchment-lined baking sheet and freeze for at least 1 hour. 
2. Combine frozen banana, milk, honey, and vanilla in food processor and process until smooth and creamy, scraping down sides of bowl as necessary. Transfer to freezer-safe container and freeze until ready to use.

To bake the cookies:

1. Heat oven to 350°. Line baking sheet with parchment paper. 
2. Combine flour, baking powder, and salt in medium bowl. 
3. In a large bowl, use an electric mixer to blend peanut butter, coconut oil, and brown sugar until smooth and fluffy. Stir in flour mixture until thoroughly combined. 
4. Working in batches, use a tablespoon to form dough into approximate 1-inch balls and place on prepared baking sheet. Gently flatten each ball into a thick disk. 
5. Bake until edges are browned and bubbling, about 10 minutes. Cool cookies for 10 minutes on baking sheet before transferring to wire rack to cool completely. 
6. Once all cookies are cooled, melt chocolate in a bowl set over a pot of simmering water. 
7. Use a teaspoon to spread melted chocolate on the flat side of each cookie and return to parchment-lined baking sheet, chocolate side up. Transfer to freezer to set, about 5 minutes.

To prepare the sandwiches:

1. Once chocolate is set, sandwich about 1 heaping tablespoon of ice cream between 2 cookies. Freeze until firm, about 30 minutes. 
2. For longer storage, wrap ice cream sandwiches in plastic wrap once firm and return to freezer.