1. Mix all filling ingredients until smooth. Split dough into two parts.
2. Starting with one portion of dough, roll into a rectangle approximately 10 by 12 inches.
3. Cut rectangle into 12 squares. Place two teaspoons of filling into each square, then fold each into a triangle. Repeat with second portion of dough.
4. Place 24 knishes onto two baking trays. Optional: brush with beaten egg and sprinkle with sesame seeds.
5. Bake for 22 minutes at 350F.