Bring a large pot of water and old bay seasoning to a boil over high heat. Lower the heat to a low, add the shrimp and cook, stirring occasionally for 2-3 minutes until the shrimp become bright pink and curl. Strain and transfer a bowl of ice water to immediately stop the cooking.

Drain and transfer the cooked shrimp to a cutting board, then chop into smaller pieces and place in a large mixing bowl.

Add the avocados, tomatoes, red onions, cilantro, lime juice and garlic. Taste and adjust to taste by adding more salt and pepper, if desired.

Serve cold with tortilla chips.