Whisk milk, flour, eggs, and 120ml water in a bowl.
Cover and refrigerate the batter for at least 20 minutes.
Preheat the oven to 220°C.
Heat beef dripping in a large pan over moderate heat.
Cook halved shallots cut-side down until softened.
Add carrots and garlic and cook until browned, about five minutes.
Transfer ingredients to an oven dish and season with thyme, salt, and pepper.
Heat the dish in the oven for five minutes until piping hot.
Tip the batter over the sizzling vegetables quickly to retain heat.
Bake for 20-30 minutes until risen and golden-brown.
Serve immediately to prevent deflation.