Finely chop onions and garlic. Melt butter to a pot over medium-high heat and fry onions and garlic until translucent and fragrant. Add sugar, salt, and pepper and deglaze with white wine.
Add chicken stock, cream, and sugar and let simmer for approx. 20 min. until sauce thickens. Season with salt and pepper to taste and garnish with parsley. Enjoy!