In a medium bowl, combine the lemon juice, lemon zest, oregano, thyme, garlic mix well. Slowly whisk in the olive oil. Add the salt and pepper and adjust to taste if desired.
Heat a grill pan over medium-high heat. Grill the zucchini for 2 - 3 minutes on each side. You want light brown grill marks on the slices. Remove from pan and set aside.