Cook orzo according to directions listed on package. Meanwhile in a medium saucepan, heat olive oil over medium heat. Add onions and saute until tender, about 3 minutes. Add in garlic and flour and cook, stirring constantly, 1 minute. While whisking slowly pour in milk and cream and season with salt and pepper to taste. Bring mixture to a simmer and cook, stirring constantly, until thickened.Mix in chopped spinach and parsley and allow to heat just until spinach begins to wilt, about 1 minute, then remove from heat and stir in Parmesan. Stir until cheese melts (returning to warm heat if needed to help melt cheese). Stir in drained orzo and serve warm garnished with additional Parmesan if desired.Recipe Source: adapted slightly from Life as a Strawberry