1 tablespoon extra virgin olive oil
2 tablespoons butter
1 medium yellow onion thinly sliced
1 tsp garlic diced
4 medium zucchini or yellow summer squash, or a mix (about 2 pounds), ends trimmed and cut into 1/2-inch-thick rounds
1/2 teaspoon kosher salt
1/4 teaspoon black pepper
1/2 teaspoon dried thyme
1/4 cup freshly grated Parmesan cheese
Heat the olive oil and butter in a large nonstick skillet over medium-low heat. Cook gently until the onions begin to brown.
Add the zucchini, salt, pepper, thyme, and remaining butter.
Increase heat to medium. Continue to cook, stirring occasionally, until the zucchini is just cooked through and beginning to brown, about 10 to 15 minutes.
Sprinkle with Parmesan. Enjoy immediately