Combine the ingredients for the sauce in a medium mixing bowl and whisk together until well-combined.* Set aside for now.
Heat 1/2 tbsp olive oil in a large non-stick skillet over medium heat.
Season steak with salt and pepper. Add to the skillet and cook for about 3 minutes, stirring occasionally, until steak is browned on all sides. Remove the beef from the skillet and set aside for now.
Add another 1/2 tbsp olive oil to the skillet, and let it heat up for a minute. Add bell pepper and broccoli and cook for about 4-5 minutes, or until both veggies are starting to get crisp-tender.
Move the veggies towards the side of the skillet, creating a little empty space. Add the last 1/2 tbsp of olive oil to that space and let heat up for about a minute. Add the shrimp to the space in the pan and cook for about 2-3 minutes, stirring occasionally, until almost cooked through.
Return the beef to the pan, then stir in the green onions and sauce mixture, tossing everything in the pan to combine. Cook for about 2 minutes, until everything is warmed, shrimp is fully cooked (pink and opaque throughout), and the sauce is slightly thickened.
For each serving, portion out 3/4 cup cooked rice, along with 1/4 of the pan of completed stir fry mixture.