Tuscan bomboloni

Name: Tuscan bomboloni
Prep time: 20 min
Cook time: 10 min
Total time: 30 min
Cuisine: Italian
Ingredients: 300 g (2 1/3 cup – 10 ½ oz) of bread flour; 200 g (7 1/8 oz) of boiled potatoes, already skinned and riced; 15 g of fresh yeast; 150 ml (2/3 cup) of warm water; 80 g (6 1/3 tablespoon - 2 ¾ oz) of sugar; 2 egg yolks; 50 g (3 ½ tablespoons) of butter, melted; Zest of 1 organic lemon; ¼ teaspoon of salt; 1 l (1 ¼ cup – 1 1/8 US quart) of frying oil