While the rice is cooking, prepare the shrimp by combining the garlic, brown sugar, soy sauce, chili powder, lime juice, red pepper flakes and olive oil in a medium bowl.
Add the shrimp, and place in the refrigerator for 10-15 minutes to marinate.
Remove the shrimp from the refrigerator, grill, or cook in a cast iron skillet on the stove, for 3 minutes per side.
When the rice is cooked, place in a large bowl, or divide between four small bowls, top with the shrimp, lettuce, tomatoes and queso fresco.
Combine all of the ingredients for the avocado cream sauce and drizzle on top.