Using your shredding blade on your food processor, shred your carrots (after peeling them), celery and onion. You can do them all in the same bowl since they're just heading for the same pot. If you don't have a food processor that shreds, you can either use a hand shredded or simply dice them finely. Mince your garlic, as well.
Heat a soup pot on medium on your stove. Once it's heated (which will help make it naturally nonstick), add the butter and let it melt. Once melted, add the carrots, celery, onion, and garlic. Saute five or so minutes until translucent, stirring periodically. Add the flour and mustard powder and stir, cooking for another three or so minutes to get out the raw taste.
Slowly add the chicken stock while stirring to avoid creating any lumps. Add the Worcestershire sauce and nutmeg and bring to a boil. Once it boils, turn down to a simmer and simmer for ten or so minutes. Use an immersion blender, puree your soup thoroughly. If you don't have an immersion blender, add soup to your regular blender in batches, never filling more than one-third full and using a pot holder, hold the lid on so pressure doesn't build up and have the lid fly off.
Once pureed, add the beer and again bring to a boil then simmer for another ten minutes.
12 ounces bottle good beer
While the soup is simmering for the last time, shred your cheeses - again, you can use the same food processor bowl and blade as before so you don't have to do as many dishes.
Once the soup has simmered for the last ten minutes, remove it from the heat and add the cheese in batches. You don't want to add more than a small handful at a time or it will just clump up into a big mess of cheese and never melt and distribute well. Instead, add a small amount and stir until it's melted and incorporated into your soup, then add your next small handful. Repeat until all your cheese is added.
2 cups shredded sharp cheddar, 1 cup shredded Gouda or Gruyere
Lastly, add the cream and stir until distributed. Serve immediately.