Start by slicing the avocados in half lengthwise and removing the pit. Scoop out a little bit of the flesh to make more room for the shrimp filling; set the scooped avocado aside.
In a large skillet over medium heat, melt the butter until it begins to foam.
Add the minced garlic and red pepper flakes to the skillet, sautéing for about 1 minute until fragrant. Be careful not to burn the garlic.
Add the shrimp to the skillet, seasoning with salt and pepper. Cook the shrimp for around 2-3 minutes on each side until they turn pink and opaque.
Remove the skillet from the heat and squeeze the lemon juice over the cooked shrimp. Toss gently to combine.
Chop the reserved avocado flesh and fold it into the shrimp mixture along with chopped parsley. Mix well.
Generously spoon the shrimp filling into the avocado halves, allowing it to mound slightly for visual appeal.
Serve immediately with lemon wedges on the side for an additional zing.