Cook zucchini noodles according to package instructions. Drain well.
Heat oil in large skillet over medium heat. Season chicken with salt and pepper and brown chicken pieces, about 3-4 minutes per side depending on the thickness. Cook in batches if necessary. Remove chicken from pan.
To the skillet, add garlic, and cook until fragrant about 30 seconds.
Add butter, oregano and lemon zest. Pour chicken broth to deglaze making sure to scrap up all the browned bits on the bottom of the pan.
Turn heat to medium-high to bring sauce and chicken up to a boil. Immediately lower the heat and stir in the parmesan cheese. Place chicken back in pan and let gently simmer for 3-4 minutes, or until sauce has slightly reduced and thickened up. Taste and adjust seasoning.
Serve warm over zucchini noodles garnish with parsley and lemon slices.
For Whole30, replace butter with ghee and omit Parmesan cheese.