[moved from Boston]
Thanks to all for your replies. I went crazy this weekend and made a few dozen, and they were SO easy. This is probably something that was better left undiscovered, since I don't really need to add tons more bacon to my diet, and yet... mmmm. Anyhow, here's the recipe I ended up with, adapted from several I found over the last week. I'm more of a cook than a baker, but this was totally fool-proof (at least for this fool).
Lithuanian bacon buns
1 cup scalded milk
1/2 cup unsalted butter
1/2 cup sugar
1 teaspoon salt
2 packages dry yeast, regular or rapid rise
2 eggs, well beaten
4 to 41/2 cups flour, sifted
1 pound lean bacon, cut into small pieces
1 medium onion, diced
1/2 pound lean ham, diced
1/2 teaspoon freshly ground pepper
1 egg yolk mixed with 2-3 tablespoons milk
Pour scalded milk into a large bowl. Add butter, sugar and salt. Let mixture cool to lukewarm, 110-115 degrees. Stir in yeast until dissolved. Add beaten eggs and then add flour gradually, mixing until dough is workable.
Turn dough onto a floured surface and knead with floured hands until smooth and elastic, about 10 minutes. Put in greased bowl, cover and let rise in a warm place until dough doubles in size, about 1 hour.
While dough is rising, make the filling.
Cut bacon into small pieces (a short stay in the freezer makes the bacon easier to cut), and fry bacon pieces in a cast iron pan until most of the fat is rendered, but the bacon is still soft (you don’t want it too crisp). Remove bacon from pan and reserve. Fry diced onions in bacon fat until tender. Reduce heat and add diced ham, stir to combine in the pan and evenly coat ham/onion mixture in the bacon fat. Once the reserved bacon cools slightly, dice it into small uniform pieces – similar to the ham – then add it back to the pan with the onion and ham. Season with pepper.
At this point, you can refrigerate the filling and dough overnight (oil the dough and seal it in a ziplock). The next day, let the dough come almost to room temp before proceeding.
On a floured surface, roll the dough into 3/8-inch thickness. Using the rim of a drinking glass or a biscuit cutter, cut flat rounds of dough until all the dough has been used. Hold a round of dough in the palm of one hand, and gently stretch it to approx 1/8-inch or 2/8-inch thickness (or whatever you'd like -- use your jugement about what thickness feels right as you fill and fold the buns). With the other hand, brush around the facing-up edge with the egg/milk wash. Place a heaping spoonful of the filling in the center, and press the edges together so you make a half-moon shaped dough pocket with the bacon/ham filling sealed in the middle. Next, brush a little of the wash along the seam and fold the two points of the half-moon under, sticking them to each other, so you form a bun shape, seam side down.
Place the filled buns (again, seam side down), on a cookie sheet lined with parchment (or you can simply grease the pan – it doesn’t matter). Put the pan someplace warm and let the buns rise 45min-1hr.
Before baking, brush buns with egg-milk mixture. Bake in a preheated 375-degree oven for 18-20 minutes or until golden brown.