Heat a wok or large, deep skillet over medium heat and add a teaspoon of olive oil.
Whisk in the eggs and cook, stirring often, until set. Transfer to a plate.
Turn heat up to medium-high. Add 1 tablespoon of olive oil and 1 tablespoon of butter to the skillet. Season chicken with salt and pepper and add chicken to the skillet. Do not crowd (overlap). Cook chicken until no longer pink; 3-4 minutes per side. Transfer to the plate with the eggs.
Add onion to the pan and cook until translucent; about 2 minutes, stirring often to avoid burning. Stir in garlic, then add frozen vegetables and cook until heated through. Season with a pinch of salt.
Add cold rice to the skillet and stir to combine with the vegetables. Press down into the pan to brown the rice lightly for a couple of minutes, then stir and repeat a few times.
Chop chicken into bite-sized pieces and add to the skillet along with the scrambled eggs. Stir to heat through.
Remove from heat, then stir in 1-2 tablespoons of soy sauce. Use more or less based on your liking.
Garnish with sesame seeds and sliced green onions and serve immediately.
Notes
Feel free to use any vegetables you like, frozen or fresh. If using fresh veggies, be sure to steam them first so they are soft. For a little extra flavor, use butter instead of olive oil.Storage: Store leftover rice in an airtight container in the fridge for 3-4 days.Freezing: Store in a freezer safe container in the freezer for up to 4 months. Thaw fully before reheating.Reheating: Place rice in a microwave safe dish and microwave for 60-90 seconds, stirring a couple of time for even heating. Or you can reheat in a pan on the stove top; add a little oil if the rice seems dry.