To make the sauce, combine all the sauce ingredients in a blender and purée until smooth. Pour into a shallow bowl and set aside.

To make the corn, hold each ear of corn upright and remove the kernels by sliding your knife down the side of the ear, rotating the ear of corn until all kernels have been removed.

Heat oil in a large frying pan over medium-high heat. Once oil is shimmering, add corn, garlic, cumin, and oregano. Season with salt and pepper and cook until corn is tender, about 2-3 minutes. Remove from heat and cover to keep warm.

Heat enough oil in a large, deep frying pan so it comes about 1-inch up the sides of the pan. While oil is heating take a stack of 2 or 3 tortillas and cut into 3-inch circles with a biscuit cutter. Repeat with remaining tortillas. Cut the scraps into pieces and fry for chips with the leftover oil when you are done.

Once oil has reached 350°F or a piece of bread dropped in the oil browns in 30 seconds, add 5 or 6 tortilla circles to the hot oil. Fry on one side until brown and crisp, then flip and repeat on the remaining side, about 3-4 minutes total.

Remove the tostadas from the oil and immediately dip in the tomato sauce. Lay on a serving platter and top each garnache with corn, a drizzling of cayenne lime mayo, and a sprinkle of cheese. Serve immediately.