Gather your mise en place; get together all of the equipment needed for the recipe and gather your ingredients.

Preheat the oven to 325°F.

Season beef with salt and pepper.

Heat oil in a heavy pot over medium-high heat. Sear beef on all sides until well browned; remove to a plate.

In the same pot, add onion, carrot, and celery. Cook for 5 to 7 minutes until fragrant and slightly softened. 

Add garlic and tomato paste; cook 1 minute more.

Deglaze with wine, scraping up any browned bits.

Return beef to pot. Add stock, bay leaf, thyme, and Worcestershire. The liquid should come about halfway up the beef.

Bring to a simmer, cover, and Low and slow, low and slow low and slow. To cook something in liquid going half way up at a low temperature, slowly until it is very tender.braise in the oven 2 – 2½ hours, until fork-tender.

Remove lid and simmer for 10 more minutes to slightly thicken.

Shred or chop beef into small, spoonable pieces. Season to taste and keep warm.

Increase the oven to 450°F.

In a bowl, whisk warm milk and eggs until frothy. Add flour and salt and whisk until smooth.

Stir in melted butter. Let the batter rest for 10 – 15 minutes. 

Place a muffin tin in the oven for 5 minutes to heat.

Remove carefully and add a tiny bit of oil, beef drippings, or butter into each cup.

Place back in the oven for 2 minutes until the fat is sizzling

Quickly fill each hot cup about ½ full with batter.

Bake at 450°F for 15 minutes.

Without opening the oven, By applying heat and evaporating the water content you are decreasing in volume and concentrating flavour.reduce heat to 350°F and bake 15 – 18 minutes more until tall, golden, and crisp. Remove from the oven and allow to cool slightly. 

Use a sharp knife to cut a small slit into the side or top. Spoon warm braised beef inside the popover, then top with caramelized onion, horseradish mayonnaise and fresh herbs (or your choice of toppings!).