Arrange the tomatoes on a wire rack and season all over with salt. Let them sit for 15 minutes before patting dry thoroughly.
Prepare the vinaigrette:
Combine the habanero and the grapefruit juice in a food processor and pulse until the habanero is finely chopped.
Transfer the juice to a bowl. Add the Dijon and maple syrup and whisk until incorporated. Taste and add more maple syrup if your pepper is quite spicy.
Whisking continuously, slowly add the extra virgin olive oil. Continue whisking until completely emulsified. Taste and season to your preferences. Set aside. Whisk before serving.
Dredge the tomatoes:
Prepare your dredging station. Gather three shallow bowls. Combine the flour, chili powder, and a sprinkle of salt and pepper in one bowl. Whisk together the eggs and heavy cream in a second bowl. Combine the breadcrumbs, cornmeal, and a sprinkle of salt in the third bowl.
Heat 1 inch of oil in a wide pot over medium heat. Pat the tomatoes dry once more. Place a tomato in the flour and shake off any excess. Next, coat it in the cream mixture. Finally, coat it with cornmeal.
Transfer to the dredged tomatoes to the hot oil. Fry for 2-4 minutes per side until golden-brown and crispy. Continue frying the tomatoes in batches. Transfer to a wire rack to cool and to allow any excess oil to drip off.
Prepare the salad:
Combine the watercress and shaved zucchini in a bowl. Toss with 1 teaspoon extra virgin olive oil and a sprinkle of salt.
To serve:
Divide the watercress salad between plates and place two tomatoes on top. Garnish with Cotija cheese. Enjoy!