Mix all dry ingredients together (flour, sugar, salt, and yeast). Lay out the dry ingredients and create a small hole in the center. Add the eggs and milk into the hole.
Using your hands, mix in the wet ingredients with the dry ingredients. Knead the dough for a minute or so. Let the dough rest. Using a stand mixer or your hands, mix in the butter in small amounts, moving slowly until everything is incorporated.
Knead the dough for 10 minutes, or until the dough no longer sticks to your hands. Cover the dough with a kitchen towel and let it rise for about an hour.
Separate the dough into small, round pieces. if you're using a kitchen scale, each piece should weigh around 35 grams. Cover the dough balls with plastic wrap.
One at a time, roll out each piece of dough into a flat, oval shape. Cover ½ of each piece with jam. Roll them up, leaving the jam on the inside.
Seal the edges and tie each roll into a knot.
Line a baking sheet with partchment paper. Place knots next to each other. Cover witha towel and let the knots rise for 40 minutes.
Preheat the oven to 350°F. Whisk the egg, milk and sugar and brush it on top of the knots. In a separate bowl, mix the flour, sugar, and butter until it forms into a crumb.
Sprinkle the knots with the flour crumbs (cover all the areas where jam is sticking out).
Bake the bulochki in the oven until they are golden brown (about 20-30 minutes). Enjoy!