Start by rinsing the long-grain white rice under cold water to remove excess starch.
In a medium saucepan, heat the olive oil over medium heat. Add the diced onion and sauté for about 3-4 minutes until translucent. Then add minced garlic and cook for an additional 30 seconds.
Add the rinsed rice to the saucepan, stirring to coat the grains. Sauté for another 2-3 minutes until slightly toasted.
Pour in vegetable broth and tomato sauce. Stir in ground cumin, chili powder, and salt to taste. Bring to a gentle boil.
Reduce heat to low, cover, and let simmer for about 18-20 minutes or until liquid is absorbed and rice is tender.
Remove from heat and let sit for 5 minutes. Fluff with a fork and squeeze lime juice over the rice. Mix in chopped cilantro if desired.
Serve warm, garnished with lime wedges on the side.