Generously season the beef cubes with salt and pepper.
In a large heavy bottomed stock pot or dutch oven, over high heat, heat the vegetable oil until it shimmers. Add half of the cubed beef to the pot and brown the beef on all sides, cooking for about 3-4 minutes total. Remove first batch of browned meat and transfer to a bowl. Repeat with the second batch of beef. Once all of the meat is browned, set it aside. It is ok if the meat is not thoroughly cooked at this point.
In the same pot with the beef drippings, reduce the heat to medium and saute the garlic for 30 seconds, until fragrant. Add in the fingerling potatoes, carrots, and celery. Saute for 5 minutes, stirring regularly.
Add in the whole can of Guinness beer to the vegetables, stir well to deglaze the meat drippings from the bottom of the pot and bring to a simmer.
Let the beer and vegetables simmer uncovered for 10 minutes. This will allow the beer to infuse the vegetables with it’s heavy dark vivacious flavour, and it will allow for some of the alcohol to cook off.
After the beer has had a chance to infuze its yummy flavor into the vegetables. Add in the diced tomatoes, tomato paste, beef consomme, water, and thyme leaves. Bring to a boil, and lower heat to a simmer.
To thicken the mixture into a stew, we are going to use a “roux”. A roux is a thickening agent made from a melted fat (butter) and combined with a thickener (flour) to create a paste that thickens anything from soups, stews, gravies, or sauces. To make the roux; melt the butter in a medium sized bowl, and add the flour to the melted butter. Stir the flour and butter mixture until a thick paste has formed. Using a soup ladle, remove about 1 - 1 ½ cups of stock from the stew that is simmering, and add that into the bowl with the flour/butter paste. Stir the stock into the flour/butter mixture until the mixture is creamy and no lumps of flour remain.
Add the roux back into the stew and stir until fully combined.
Add the browned beef back into the pot, cover the stew and let it simmer for 30-45 minutes, stirring regularly making sure nothing is sticking to the bottom of the pot.
Whipped It Up - https://whippeditup.com/guinness-beef-stew/