Rinse 1 cup of jasmine rice under cold running water until the water runs clear. Drain well and set aside.

Combine the rinsed rice, 1 1/2 cups of water, and 1/2 teaspoon of salt in a medium saucepan. Bring to a boil, reduce heat, cover, and simmer for about 15 minutes. Let sit covered for an additional 5 minutes.

Heat a skillet over medium heat and add 1 tablespoon of olive oil and 1 tablespoon of unsalted butter. Once melted, add sliced onion. Cook for 15-20 minutes until golden brown.

If using garlic, add 1 clove of minced garlic during the last 2 minutes of cooking the onions.

Fluff the cooked rice gently with a fork. Add 2 tablespoons of unsalted butter to the warm rice, mixing until fully melted.

Fold the caramelized onions and 1 tablespoon of chopped parsley into the rice, and toss gently.

Transfer the rice to a serving bowl while warm, and garnish with additional herbs if desired.