In a large pot, cover the potatoes with cold water and bring to a boil until tender and easily pierced with a fork, 10 to 15 minutes. Drain and allow to cool until cool to the touch. Cut in half and set aside in a large bowl.
In a separate bowl, combine the mayonnaise, mustard, agave, red pepper flakes, lemon juice and onion. Stir to combine, then taste and adjust the seasoning. Pour the sauce over the potatoes and mix until thoroughly combined. Pour the potatoes on a serving platter. Garnish with the basil, microgreens and hot sauce.