In a large bowl, dissolve yeast and plain sugar in warm water. After 10 minutes, add 3/4 cup of the brown sugar, the milk, butter, syrup, and eggs/yolks. Stir well, add flour and salt.
Form a rough ball and knead until smooth. Grease a bowl with oil, add the dough and let rise 1 hour.
Place dough on a floured surface and knead briefly. Roll out into a 10x16 rectangle, sprinkle with blueberries and remaining brown sugar. Roll tightly. Cut into 12 even slices, and squeeze into muffin pans (use two 6 hole pans so that they have room to expand.).
Set aside to rise 15 minutes while your oven preheats to 350. Bake 35 minutes, till golden. Cool, dust with powdered sugar.