Make the sauce: To a pan over medium heat, add the olive oil and unsalted butter. Once the butter is melted, add the diced yellow onion and red bell pepper and cook until softened. Add the garlic and thyme leaves and cook just until fragrant. Stir in the crushed tomatoes, heavy cream, grated parmesan, chopped basil, dried oregano, salt, pepper, and red vinegar. Let everything simmer for a few minutes to bring the flavors together.

Blend the sauce: Use an immersion blender directly in the pan and blend until completely smooth. If using a regular blender, carefully transfer the sauce and blend until smooth.

Prep the vegetables: Thinly slice the zucchini, Roma tomatoes, yellow squash, and Chinese eggplant into even rounds. You can use a mandolin slicer for quick, uniform slices or do this manually with a sharp knife.

Assemble: Spread the blended tomato sauce evenly across the bottom of a 12 inch circular baking dish. Arrange the sliced vegetables upright in a tight, circular pattern, starting from the outer edge and working your way inward until the center is filled. Drizzle lightly with olive oil and season with salt and pepper.

Bake: Cover with foil and bake at 375°F until the vegetables are tender, about 30 to 35 minutes. Uncover and bake another 15 to 20 minutes until lightly caramelized on top.

Finish: Let rest for a few minutes before serving. Garnish with chopped parsley and an extra drizzle of olive oil if desired.