Pat chicken dry with a paper towel and season both sides with salt, black pepper, dried oregano, and dried basil.

Heat olive oil in a large skillet over medium-high heat until shimmering.

Carefully lay chicken into hot oil and cook undisturbed for 5 to 7 minutes per side until golden-brown.

Transfer chicken to a plate and set aside.

Reduce the heat to medium and add sliced onion to the skillet, stirring to coat in residual oil and pick up browned bits.

Cook onion for about 2 to 3 minutes until softened. Add minced garlic and stir immediately for 30 to 45 seconds.

Add sliced mushrooms to the skillet and cook for 4 to 5 minutes, stirring every minute until golden.

Stir in sliced zucchini and cook for 3 to 4 minutes until tender but not mushy. Season lightly with salt and pepper.

Nestle seared chicken back into the skillet and pour in chicken broth. Bring to a gentle simmer.

Reduce heat to medium-low and cook for 5 to 6 minutes, turning chicken halfway through.

Remove from heat and scatter grated Parmesan over the top to melt. Garnish with freshly chopped parsley and serve immediately.