Sprinkle the yeast over the water and let rest at room temperature for 5 minutes. Meanwhile, warm milk and butter in a small saucepan on the stove top until the butter is melted. Combine the milk and melted butter with sugar in a large heat-proof mixing bowl and whisk until the sugar is completely dissolved.
Let the milk mixture cool until it is just warm to the touch – NOT HOT.
Add the yeast and water to the milk mixture, stirring to combine. Add the salt and three cups of the flour all at once, stirring until all the flour has been absorbed. Use your hands to combine the ingredients if you’re having trouble incorporating the last of the flour. The dough will be sticky, but should come together in a shaggy ball. If it’s still more the consistency of cookie batter, work in up to an additional 1/2 cup of flour. Cover the dough and let it rise until it has doubled in size, about 1.5 hours.
Lightly grease 1 bundt pan or 2 loaf pans with butter (if using 2 loaf pans, you can cover and freeze one - just bring the frozen one to room temp before baking). Preheat the oven to 350 degrees F.
Combine apples, brown sugar, nuts, cinnamon, and lemon juice and zest, stirring to combine well.
Lightly dust your hands with flour to prevent the dough from sticking. Gently pull pieces of dough that are roughly 1/4 cup in size and flatten them into disks. (The dough will be sticky, but add a bit more flour to your palms if needed. No need to be terribly precise here.) Inside each disk of dough place 1 heaping tablespoon of apple filling, and pinch the edges closed around the filling to form a ball. Line the filled dough balls up in your prepared baking dish to form a base layer. Sprinkle about 1/4 cup of apple filling over the base layer of dough. Repeat, forming additional layers of dough and apple filling until the pan is filled to about 2 inches below the top. Scatter any remaining apple filling over the top.
Bake on the lowest rack, until golden brown on the surface, 30-35 minutes. If the surface begins to turn dark brown, lightly cover the pan with foil and continue baking until the bread is cooked through. Allow to cool for 10 minutes before serving.