Cut the each potato in half and put in a pot, cover with water.
Salt the water and bring to a boil, boil for 15 minutes. Blanch when done
in a medium size bowl mixed together onions and peppers
in another medium bowl whisk together dijon, vinegar, olive oil, salt and pepper. Taste and add lemon juice as needed.
Toss the peppers and onions with the potatoes, then add dressing and toss some more.
Season the non skin side of the mahi mahi steak with salt, pepper, dill and lemon juice.
Place the steak skin side up in a pan heated at medium high with olive oil. Season the skin side with salt, pepper, dill and lemon juice
Cook the steak 2-3 minutes, flip and cook another 2-3 minutes
Cut the kaiser bun in half, put a bed of arugula on the bottom half, then the steak. Coat the top half of the bun with tartar sauce, add the tomato slice.