I did not request mayo on mine. I snuck into the kitchen at RUB last Monday and grabbed a Guberburger with hot, melted peanut butter only. RUB's Monday Night smashed burger, cooked on a flattop with a generous sprinkle of salt, and served on a toasted, buttered bun is phenomenal. The addition of peanut butter to this burger made me delirious. The beefy, salty, p-nutty flavor profile may have even been better than the original.
This Monday night's burger (tomorrow) will be RUB's nod to the Jucy Lucy of Minneapolis, a burger with a hot cheese surprise inside. Take a bite too soon and I can guarantee pain. I've tried to make the Jucy Lucy at home only to fail miserably. I'll be there tomorrow for sure and hope they are more successful than I've been.