Start by gathering all your ingredients. If using frozen shrimp, thaw them under cold running water or in the refrigerator overnight. Chop the garlic finely and set aside. Rinse the broccoli florets and cut them into bite-sized pieces.
In a large skillet, heat 1 tablespoon of olive oil over medium-high heat. Add the broccoli florets and sauté for about 3-5 minutes, until they are bright green and tender-crisp. Remove them from the skillet and set aside.
In the same skillet, add the remaining olive oil along with the unsalted butter. Once the butter has melted, add the minced garlic and sauté for about 30 seconds until fragrant. Then, add the shrimp, seasoning them with salt, pepper, and red pepper flakes if using. Cook for 2-3 minutes on each side until the shrimp are pink and opaque.
Return the broccoli to the skillet with the shrimp. Add the lemon juice and toss everything together until well combined and heated through. Taste and adjust seasoning if necessary.
Serve the Garlic Butter Shrimp and Broccoli hot, over a bed of rice or pasta, or simply on its own. Enjoy the wonderful flavors and the beautiful colors on your plate!