You can also call this sandwich "The King," because it may be one of the most over-the-top indulgent treats ever. Thick, rich, and nutty peanut butter ice cream is paired with soft banana oat cookies. The best part, however, is the crumbled bacon around the edges of these sandwiches. One bite will have you talking like Elvis: "Thank you, thank you very much."
Prepare an ice bath by filling a large bowl with ice cubes and 1 to 2 cups of water. Place a medium bowl fitted with a fine strainer inside the ice bath.
In a medium saucepan set over medium heat, melt the peanut butter until thinned and smooth. Add the milk, cream, ½ cup sugar, salt, and vanilla, and stir. Cook for another 2 to 3 minutes, or until the mixture is warmed.
In a medium bowl, whisk together the egg yolks and the remaining ¼ cup sugar. Carefully whisk 1/2 of the warm milk mixture into the egg yolks, 1 ladleful at a time, until the egg mixture is warmed. Whisk the egg-milk mixture back into the saucepan. Cook the mixture over medium heat, stirring constantly with a wooden spoon, until the mixture is thick enough to coat the back of the spoon and registers around 175 degrees on an instant-read thermometer, about 5 to 7minutes. Be careful not to boil the mixture.
Immediately strain the mixture through the fine strainer into the prepared ice bath. Cool the custard in the ice bath until it reaches room temperature, stirring often. Press plastic wrap against the surface of the custard and refrigerate until chilled, about 4 hours or up to 1 day.
Pour the chilled mixture into an ice cream maker. Freeze according to the manufacturer’s directions. Transfer the ice cream to an airtight container, press plastic wrap against the ice cream surface, and freeze until it is firm and the flavor is ripened, at least 2 hours.
Preheat the oven to 350 degrees. Line baking sheets with parchment paper or silicone baking mats.
In a small bowl, whisk together the flour, oats, baking soda, and salt.
In a large bowl, mix the butter and sugars with a rubber spatula. Add the egg and egg yolk, stirring to combine. Stir in the mashed bananas, vanilla, and cinnamon. The mixture will be lumpy. Gradually add the flour mixture and stir until everything is thoroughly combined.
Using a spoon or spring-loaded scoop, drop 2 tablespoon-sized balls of dough onto prepared baking sheets. Flatten slightly with the palm of your hand. Chill the dough in the refrigerator for 30 minutes.
Bake for about 11 to 12 minutes, or until the edges are slightly browned. Let cool on baking sheets for 5 minutes before removing to wire racks to cool completely. Freeze the cookies until frozen, at least 1 hour. Cookies can be stored in airtight containers in the freezer for up to 1 month.
To assemble, place the bacon in a shallow dish. Top 1 cookie with a scoop of ice cream. Place another cookie on top of the ice cream and gently press down to forma sandwich, allowing the ice cream to ooze out the sides slightly. Roll the edges in the crumbled bacon. Immediately place the sandwich in the freezer. Repeat for the remaining sandwiches. Freeze the sandwiches until firm, at least 1 hour, before serving.