Beef and Rutabaga Pasties

From the garden

• 1 medium rutabaga (swede), peeled and cut into 1/4-inch dice
• 2 medium waxy potatoes, peeled and cut into 1/4-inch dice
• 1 medium yellow onion, finely diced

From the pantry

• 1 lb ground beef (or skirt steak, finely diced)
• 3½ cups all-purpose flour · plus more for rolling
• 14 tbsp butter, cold, cut into cubes · 12 tbsp for the pastry, the rest dotted over the filling
• 1 egg, beaten · for the wash
• salt · to taste
• black pepper · a pasty wants a heavy hand

1. Rub 12 tablespoons of the cold butter into the flour with a teaspoon of salt until the bowl looks like coarse crumbs with some pea-sized pieces left. Add ice water a tablespoon at a time, roughly 8, until it gathers into a dough.
2. Press the dough into a flat disc, wrap it, and chill at least 30 minutes. Handle it lightly: pasty pastry has to stay sturdy enough to carry a raw filling through a long bake without splitting.
3. Toss the rutabaga, potato, onion, and beef together with a scant tablespoon of salt and a great deal of black pepper. Everything goes in raw and cooks inside the pastry, which is where the gravy comes from.
4. Roll the dough into four rounds about 8 inches across. Pile a quarter of the filling on one half of each, dot with the remaining butter, leave a clear border, and brush that border with water.
5. Fold the pastry over, press the air out, and crimp the edge into a rope with small overlapping tucks. Set the pasties on a lined sheet pan, brush with egg, and cut a steam vent in each.
6. Bake at 400°F for 15 minutes, drop the oven to 350°F, and bake 35–40 minutes more, until deep golden. Rest 10 minutes, since the filling comes out molten and needs to settle.