In medium size sauce pan, boil potatoes until fork tender, 10-15 minutes. Drain, cover and chill until ready to use.
In a large mixing bowl, combine all ingredients (except corn and sweet potatoes) and mash with a fork (if mixture is too dry, add some of the reserved bean liquid). Add corn and sweet potatoes and gently shape into patties and cover; chill at least 1 hour and up to 1 day.
Heat a large pan over medium high heat and add the olive oil. Cook the patties for 5 minutes on each side. Transfer to platter.
Serve sliders on top of a bed of greens and salad toppings, or fill in lettuce leaves and eat as wraps, or in a bun with all the fixings.