First, slice the potatoes, zucchini, and eggplant into thin, broad slices.
Slice the peppers into strips.
Heat oil in a skillet and toss in the chopped veggies. Remove them when they are all dente, which means they are firm when you bite them. Season with salt.
Preheat the oven to 350ºF or roughly 175ºC.
PlacePlace a square cooking or baking mold/form on a tray and layer it with the sliced potatoes, zucchini, eggplant, and peppers. Bake for 35 minutes at 350ºF or 175ºC.
Remove from the mold and cut into smaller squares. Ensure they are small enough for a bite. That will make them easy to handle and eat.
Cut two thin strips of zucchini and place them in a cross shape. In the center, put the baked veggie squares. Fold the zucchini over the veggies to make a little packet. Use a toothpick or a wooden skewer to keep it together.
Next, coat it with tempura mix and fry it in hot oil.
Plate it up, decorating the plate with a spoonful of aioli and another of tomato sauce. Finish by placing the skewer in the center and serve.