In a medium saucepan, bring water to a gentle boil. Add the pearl couscous and butter. Return to a boil, then reduce heat to a simmer. Cover and cook for 10 minutes, until al dente. Drain off any remaining liquid and set aside.

Meanwhile, set a large skillet over medium-high heat and add olive oil. When the oil is hot, add the chopped onion. Cook for 3 minutes, stirring frequently until softened.

Add the minced garlic to the skillet and cook for an additional 30 seconds, until fragrant.

Stir in the thawed and drained spinach, salt, and black pepper. Cook for 2-3 minutes to heat through and combine flavors.

Add the cooked couscous to the spinach mixture. Stir well to combine all ingredients evenly.

Adjust seasoning to taste and serve