Preheat about 5 cups of oil in a medium sauce pot, over medium to medium-high heat. Heat oil to about 315 degrees. (350 will cook doughnuts too fast on the outside and leave them raw on the inside.)
Set out a wire rack and cover it with a paper towel or two.
In a large mixing bowl, whisk ricotta, vanilla, sugar and eggs until all incorporated.
Add flour baking soda and salt. Mix with a rubber spatula until completely mixed throughout.
Lay out a piece of parchment paper and lightly grease it.
Grease your hands with some cooking spray as well. Scoop out some dough and make about 1-inch balls. Lay them on the parchment paper while waiting to be fried.
Fry doughnut balls in batches of about 6 (as fitting to your sauce pot) for 5-7 minutes, until deep golden brown.
Take out the cooked doughnut balls and place them on a paper towel. After they are cooled for a couple of minutes, dust them with powder sugar.