In a small bowl whisk together all ingredients for marinade. Place half of marinade into a larger bowl and add shrimp. Toss to coat and let sit for 15 minutes. Set remaining marinade aside to use as a sauce.

To slice oranges, remove top and bottom with a sharp knife so that some of the flesh is visible. Place one flat end on cutting board and slice away the peel in sections, removing as much white pith as possible. Once all the peel is removed, cut away any excess pith left behind. Cut orange into cross-sections, and then cut each into quarters.

To cook the shrimp, heat vegetable oil in a large skillet over medium high heat. Add shrimp but do not over overcrowd the pan, work in batches if needed. Cook for 1-2 minutes on each side, until shrimp turns pink and opaque.

To serve, add cooked rice to bowls. Top with cooked shrimp, orange chunks, avocado, and scallions. Drizzle reserved sauce over the top and serve.