Wash the broccoletti in cold running water. The entire plant is edible, so you don't have to remove anything.
Place a steamer basket in a pot with a small amount of water. Cover the pot with a lid and bring the water to a boil.
Arrange the broccoletti in the steamer basket.
Steam the broccoletti for about 5 minutes or until they are tender but still have a slight crispness.
Transfer the steamed broccoletti into a bowl of icy water to stop cooking and preserve the vibrant green color. Let it sit for 10-15 seconds, then transfer it to a serving dish.
Heat butter and olive oil in a small pan over medium heat.
Add minced garlic and sauté for 1 minute until it becomes fragrant. Be careful not to burn the garlic. Add salt per your taste.
Drizzle the sautéed garlic and olive oil over the broccoletti.
Toss the broccoletti gently to coat them with the garlic sauce.
Squeeze fresh lemon juice over the broccoletti before serving.
Serve the steamed broccoletti as a side dish alongside your favorite main course.