To make the sauce, lightly coat the jalapeno with cooking oil and roast on the gas grill or a 450°F oven until charred. Remove the seed if you like a milder sauce. Combine the roasted jalapenos, cilantro and ½ of the mayonnaise in a blender and puree to a chunky to smooth texture. Stir in the remaining mayonnaise and place the sauce in a serving bowl and set aside.

To make the tempura sauce, combine the flour, egg yolk and very cold water in a cold bowl and beat with a wire whip or mixer until smooth. Place the batter in the refrigerator while you prepare the avocado slices. This batter needs to be very cold to produce a crisp tempura crust.

Line a baking sheet pan with parchment paper and set aside. Combine the Panko crumbs and salt in a pie dish and set aside.

Cut avocados into halves and remove the seeds. Cut each half into 6 slices. Dip each avocado slice in the chilled tempura batter, coat with Panko crumbs, shake and place on the prepared sheet pan.

Heat the oil in a deep fryer or heavy bottom skillet to 325°F. Fry 4 to 6 coated avocado slices at a time for 1 minute or until golden brown. Salt to taste.