In a large bowl, whisk together the eggs, heavy cream, 1 teaspoon of salt, and the ricotta. Set aside.
Heat a 12-inch (30 cm) cast-iron or stainless steel skillet over medium-high heat. Add the bacon and cook until crisp, 3-5 minutes. Using tongs, transfer the bacon from the pan to a paper towel-lined plate, leaving the rendered bacon fat in the pan.
Add the onion to the pan and cook until caramelized, 8-10 minutes.
Add the garlic and red pepper flakes and cook until fragrant, about 30 seconds. Add the zucchini and sauté until starting to soften, 2-3 minutes.
Add the corn and cook for 2 minutes, stirring occasionally, until the zucchini softens further but is still bright green. Season with the remaining teaspoon of salt and the pepper.
Pour the egg mixture over the vegetables, then top with the bacon.
Transfer the skillet to the oven and bake for 12-15 minutes, until the top is puffed and the eggs are cooked through.
Garnish with parsley, then serve directly from the skillet.