Caraway-Onion-Garlic Rye Bread

1. Combine the yeast, sugar, caraway seeds and milk in a bowl.
2. Melt the butter.
3. Optional: Sauté the onions in butter, stirring frequently until they just start to brown. Then add the garlic and cook another minute. Allow to cool below 110ºF.
4. Mix the salt, rye flour and 1 1/2 cups all-purpose flour in a bowl.
5. When the yeast has proofed, add the yeast mixture to the dry ingredients.
6. Add the melted butter and 1 beaten egg, then stir. (Mix the remaining beaten egg with the water and set aside to use as the egg wash.) If using, add the cooled onions and garlic.
7. Turn onto a floured surface and knead. Gradually add the rest of the all-purpose flour and continue to knead until smooth, about 8 minutes.
8. Form the dough into a smooth ball. Lightly oil a bowl. Place the dough in the bowl and turn it to all sides with oil. Cover with plastic wrap and set aside in a warm, draft-free place until it doubles in size, about 1 hour.
9. Preheat the oven to 350ºF and lightly grease a 5 1/2 by 9-inch loaf pan.
10. Punch down then turn the dough onto a lightly floured surface.
11. Gently knead the dough several times.
12. Form to roughly fit the loaf pan. Pinch to seal any seams in the dough and place in the prepared loaf pan. Use your fingers to get it in the corners. Cover with a light towel and set aside in a warm, draft-free place until it doubles in size, about 45 minutes.
13. Brush the egg wash lightly over the top of the dough.
14. Slash the surface with a sharp knife.
15. Bake until lightly brown, about 40 minutes.
16. Remove from the oven and pan then cool on a rack.