Separate egg yolks from egg whites from 2 large eggs.
Beat 2 egg yolks with 1 3/4 cups of sugar.
In a little bowl, squeeze out juice from 1/2 a lemon, and mix it with 1/2 teaspoon of baking soda. It will foam, add to the eggs and sugar.
Add 2 cups of sour cream to the mix. Beat all together.
On low speed, mix in 3 cups of flour.
The dough will be a bit sticky. Transfer into a bowl, cover, and put in the freezer for 1 hour.
After an hour take the dough out. Preheat your oven to 350F. Prepare 2 baking sheets with parchment paper (you can also just spray with oil).
Wet your hands, this will help you roll the batter into balls easily. Make balls and place on cookie sheets. Leave room between each ball.
Bake for 20 minutes or until the the bottom of the cookies start to get a brownish color.
While the cookies are baking, make the glaze: With a hand mixer beat together 2 egg whites for 1 minute. Then add 2 1/2 cup of powdered sugar and beat until well incorporated.
When you take out pryaniki from the oven, let them cool down for a few minutes. Brush the glaze all around each cookie. (The glaze will dry fast on the cookies, so brush the tops, let dry, then flip over and glaze the bottoms.)
Store either in a ziploc bag or in a covered dish.