Pre-heat the oven to 425°F. Roll out the pastry into a 12-inch square. Set aside four 2-cup bowls; invert 1 bowl onto the pastry and cut out 4 rounds. Place on a parchment-paper-lined baking sheet and brush with the egg. Sprinkle with coarse salt and the caraway seeds. Bake the rounds until golden, about 12 minutes. Let cool.
In a large saucepan, add the potatoes and enough water to cover. Bring to a boil, salt the water and cook until tender, 7 minutes. Add the peas and cook for 1 minute; drain.
In a large, deep skillet, cook the bacon over medium-high heat until crisp, about 4 minutes. Drain off half the fat, add the beef to the skillet and cook, breaking up the meat, until browned, 5 minutes. Add the shallots and garlic and cook until softened, 3 minutes. Stir in the Worcestershire sauce. Make a well in the center, add the butter to melt, then whisk in the flour. Whisk in the beef broth until thickened, about 1 minute. Season with salt and pepper, then stir in the horseradish, cream and parsley; cook until thickened, 1 minute. Turn off the heat; fold in the potatoes and peas. Fill the bowls with the meat and potatoes and top with the crust.