Line 9 x 5 inch loaf pan with parchment paper large enough so there is a 1 inch overhang.

In food processor container, place banana; turn machine on and let it run until banana is reduced to the size of small pebbles. Scrape down sides of bowl; add raspberries, peanut butter, vanilla, and salt; continue blending until creamy. Be careful not to overblend to the point where bananas begin to melt. Pulse in peanuts.

Place banana mixture in pan and spread out into an even layer. If desired, sprinkle some additional peanuts on top. Place in freezer until frozen solid, at least 4 hours.

Using parchment paper overhang, lift frozen block out of pan and, using serrated knife, carefully slice into 8 bars. Store in airtight container in freezer for up to 1 month.