In a large bowl add shrimp, dried oregano, chili powder, ground cumin, garlic powder, salt and pepper. Mix thoroughly until shrimp is well combined. Set shrimp aside
Cut cucumbers into thin slices with a knife or mandolin. Remove husks from corn. Add water to a large pot (About half way full or at least enough to cover corn) and boil. Then add corn and cook for 5-7 minutes. Remove corn from water and pat try. Use a knife to carefully shave off corn kernels. Season kernels with a little salt/pepper to taste.
Heat skillet over medium heat. Add unsalted butter. When butter has melted add the seasoned shrimp. Arrange shrimp in a single layer to allow to cook evenly. Cook shrimp for 2-3 minutes and then flip over. Continue to cook for another 2-3 minutes or until shrimp
Arrange salad by Add salad to bowl and layer on shrimp, cucumber slices, tomatoes, corn and avocado.