Wash shrimp and dry with paper towels. Season with ΒΌ tsp salt, pepper and garlic powder. Mix well. Heat a pan to cook the shrimp. When the pan is hot, add 2 tbsps of olive or vegetable oil to coat the bottom of the pan. Place shrimp in a single layer and cook for 2 to 3 minutes until done. Turn shrimp halfway through cooking. Remove shrimp to a plate and set aside. Cook in 2 batches if your pan is not large enough to hold all shrimp in a single layer.
In a measuring cup, whisk lemon juice, orange juice, mustard and salt/ground black pepper to taste. Add olive oil and whisk to combine.
Cut cherry/grape tomatoes in half. If using large tomatoes, cut into bite size pieces. Place tomatoes on serving plate and top with onions and parsley. Pour a little bit of the dressing all over. Add shrimp to the plate as well as sliced avocado. Pour some of the dressing over avocado and shrimp.
Salad will serve 4 people as a side or 2 people as a meal.
There may be some dressing leftover. You can also serve the whole salad on a bed of romaine lettuce and coat the lettuce in some of the dressing.