German Onion Pie (Zwiebelkuchen)

Ingredients

• 1 ½ cups all-purpose flour
• ¼ cup + 1 tbsp warm milk
• ½ tsp salt
• 4 tbsp softened butter (cubed)
• 1 package active dry yeast
• 2 tbsp butter
• 2 ¼ lbs yellow onions (diced)
• 5 slices thick bacon (diced)
• 1 ½ cups sour cream
• 4 large eggs
• 2 tbsp flour
• 2 tsp salt
• 1 tsp caraway seeds
• Fresh ground black pepper