Yorkshire mini puddings with roast beef and caramelized onions

Ingredients:

• 3/4 cup whole milk
• 2 large eggs
• 2/3 cup premium flour
• 1 yellow onion, thinly sliced
• 1/4 teaspoon granulated sugar
• 220 g thin slices of roast beef
• 2 tablespoons prepared horseradish sauce
• 1 tbsp chopped fresh chives, for serving
• Special equipment: 24-cup mini-muffin pan

Preparation:

1. Preheat the oven to 200°C (400°F). Place a mini muffin tin on a rimmed baking sheet. Pour enough vegetable oil into each muffin cup to coat the bottom. Place in the oven while it preheats.
2. In a large liquid measuring cup, combine the eggs and milk. Add the flour, 1/4 teaspoon salt, and 1/4 teaspoon black pepper and whisk until smooth. Set aside.
3. Heat a skillet over medium-high heat. Add 1 tablespoon of vegetable oil and the onion. Cook, stirring frequently, until the onion begins to soften. Add the sugar and 1/4 teaspoon of salt. Continue cooking until the onion is lightly browned and softened, about 10 minutes. Turn off the heat and set aside.
4. Carefully remove the hot pan from the oven. Pour the batter into the muffin cups, filling each cup about three-quarters full. Bake until the puddings are fluffy and golden brown, about 20 minutes; do not open the oven, or the puddings may collapse.
5. Transfer the Yorkshire puddings to a serving platter. Top each with a few caramelized onions.
6. Cut the roast beef in half or into thirds and arrange the pieces on top of the onions. Drizzle each serving with about 1/4 teaspoon of horseradish sauce and sprinkle with finely chopped green onions.