To make the marinade combine 1/4 cup olive oil, 2 grated garlic cloves, 1/2 cup chopped cilantro, zest of 1 lime, juice of 1 lime, 1 tsp chili powder, 1/4 tsp black pepper, and 1/4 tsp salt.
Place the shrimp into a large zip lock bag and pour the marinade over the shrimp. Close the bag tightly and shake it around to to evenly coat the shrimp. Place in the refrigerator for at least 1 hour or overnight.
Meanwhile make the dressing by combining 2 tbsp olive oil, juice of 1 lime, 1/3 cup cilantro, 1/4 tsp black pepper, 1/2 tsp salt or to taste, and 1 grated garlic clove. Then set aside.
Make the quinoa by adding 2 cups water, 1 tbsp butter, and 1 cup (rinsed) uncooked quinoa in a saucepan. Bring it to a boil the cover and bring the heat down to low. Cook until all the liquid is absorbed (about 15 minutes).
Place the marinated shrimp on wooden or metal skewers. Grease the grill and cook the shrimp on high for about 4 minutes per side.
Assemble your bowl by placing your desired amount of chopped avocado, cherry tomatoes, corn, red onion, quinoa, and grilled shrimp. Then drizzle generously with dressing.