Devein and peel the shrimp, but keep the tail on. Make 3 or 4 slits on its underside.
Bend back the shrimp backwards (bending the outer curve) until you feel a slight pop along each section. Make small incisions to cut the sinew, and pull the shrimp straight.
Slice the eggplant in half lengthwise. Leaving about 2 cm of the stem ends, and make about 5 mm wide cuts along the length of the eggplant Soak in water and drain.
Scoop out the seeds and fluffy insides of the kabocha squash, and chop into 5 mm wide pieces. Remove the stalks of the shiitake mushrooms and cut in half.
Peel the lotus roots and slice into 5 mm wide pieces. Soak in water with a little vinegar and drain.
Put some mayonnaise into a bowl. Add water in batches and mix well. When mixed evenly, add the flour. Stir until it's still slightly floury.
Dredge ingredients prepped in Steps 3, 4, 5, 6, and shiso leaves in the batter prepped in Step 7. Deep-fry in vegetable oil.