Rinse the rice under cold water until mostly clear; drain well.
Warm olive oil and butter in a medium saucepan over medium heat.
Cook the onion until softened and translucent, about 3 minutes.
Stir in turmeric, cumin, and garlic powder; toast 30 seconds.
Add the drained rice and stir to coat evenly, about 1 minute.
Pour in broth, add salt and pepper, and bring to a lively simmer.
Reduce heat to low, cover, and cook until liquid absorbs, 15–17 minutes.
Turn off heat, fold in peas, cover, and rest 5 minutes.
Fluff with a fork and serve warm.