Mix all dry ingredients together (flour, sugar, salt, yeast). Create a small area in the center of it and to it, add eggs and milk.
Using hands, mix in liquid into the flour. Knead the dough for a minute or so. Let the dough rest. Now, using a Kitchen Aid mixer or your hands, mix in butter in small amounts (about 15 grams). Do it slowly, until everything is mixed in.
Knead the dough for 10 minutes, until the dough no longer sticks to the 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 them with plastic while you work on making knots.
Roll out each piece into a flat, oval shape. Cover ½ of each piece with jam. Roll them up, leaving jam on the inside.
Seal the edges and tie each roll into a knot.
Butter up the bottom of the tray, sprinkle it with gram crackers grumps. Place knots next to each other. Cover with towel and let it rise for 40 minutes.
Preheat the oven to 350F. Whisk egg, milk and sugar and apply it to the knots, brushing it on. In a separate bowl, place flour, sugar and butter. Make crumbs out of it.
Sprinkle the knots with flour crumbs (cover all imperfections of the jam sticking out).
Bake them in an oven, until they are golden brown; 20-30 minutes.