Defrost shrimp according to recommended thawing instructions if using frozen.
Heat olive oil in a large skillet over medium heat.
Add diced onion and minced garlic to the skillet and sauté for 2-3 minutes until fragrant.
Pour white wine or chicken broth into the pan and let reduce for 5 minutes.
Add shrimp to the skillet and cook for 2-3 minutes until heated through the center, being careful not to overcook.
Stir in butter, oregano, and parsley until butter melts completely.
Season with salt and black pepper to taste.
Serve immediately with your favorite pasta or rice.