Mash with the butter, milk, salt, pepper, and nutmeg. The texture should be fluffy but firm enough to sit on top of the pie.
Make the filling
5 Heat the butter or dripping in a large skillet over medium-high heat.
6 Brown the beef well, breaking it into fairly small pieces. Let it actually develop some color before stirring too aggressively.
7 Add the carrots, celery, and mushrooms. Cook 7-10 minutes until the vegetables soften and the mushrooms have given up most of their moisture.
8 Add garlic and asafoetida and cook about 30 seconds.
9 Stir in the tomato paste, Worcestershire, thyme, black pepper, and salt. Cook the tomato paste for another minute.
10 Add the Scotch. Let it bubble vigorously for 30-60 seconds.
11 Add the beef stock and simmer about 10 minutes, until the filling is moist but no longer soupy.
12 If it remains loose, sprinkle in the flour and cook another 2-3 minutes.
13 Taste and adjust seasoning.
Assemble
14 Transfer the filling to a roughly 2 1/2- to 3-quart baking dish.
15 Spoon the clapshot over the top and gently spread it to the edges. Rough up the surface with a fork so you get lots of browned peaks.
16 Bake at 375°F for 25-30 minutes, until bubbling around the edges.
17 For extra browning, give it 2-3 minutes under the broiler at the end.
18 ⸻
2. Crispy Skirlie
19 You can make this while the pie is baking.
20 Melt the butter or dripping in a skillet over medium heat.
21 Add the oats and cook, stirring frequently, about 6-8 minutes. You’re looking for toasted, nutty oats rather than crunchy granola.
22 Stir in the asafoetida, thyme, pepper, and salt.
23 Continue cooking another 2-3 minutes until fragrant and lightly browned.
24 Serve a spoonful over each portion of cottage pie.