MADE: Guinness Shepherd's Pie

I currently live in a city that is rainy and grey for most of the winter months. When I come home from a day that never got sunny, I just can't bear the thought of anything less than a blanket-like dinner in which to wrap myself (figuratively--don't worry) and forget the grim exterior conditions.

For inspiration, I figured I'd turn towards cuisine of similarly-climated locales, and shepherd's pie seemed like a no-brainer. If it's good enough to fortify soggy peasants in Ireland, then it can help me soldier on through the Seattle winter. Tossing in a portion of my leftover bottle of Guinness seemed like a logical addition, for similar reasons. (It turned out to be not only logical, but DELICIOUS as well--but I'm putting the cart before the horse. Perhaps several carts before several horses.)

Guinness Shepherd's Pie

Brown Sauce Filling
4 tbsp butter, divided
1/2 small onion, diced
1 tsp salt
1 tsp brown sugar
10 (or so) white mushrooms, chopped coarsely
1/4 cup flour
1/2 cup Guinness
1 cup water
Salt and pepper, to taste

Melt 1 tablespoon of butter into a skillet. On medium heat, caramelize the onions--stir in the salt and sugar to bring out the natural sugar of the onions themselves. Stir the onions occasionally, and if they begin to stick to the pan, add about 1/4 cup water and stir vigorously for about 30 seconds. This is called "deglazing," and it's one of my favorite science-cooking processes. (Second only to bechamel, which we'll get to in a minute...) Continue the stir/simmer/deglaze process for about 15 or 20 minutes, until the onions start to become darker brown and smell delicious. Then add the chopped mushrooms and stir, simmering until the mushrooms become a little softer, but not mushy.
Meanwhile, (probably while the onions are caramelizing, actually, since you'll be bored anyway) melt 3 tablespoons of butter in a medium saucepan. Once the butter is just beginning to sizzle, add 1/4 cup flour and whisk or stir rapidly, until thoroughly mixed. Then, quickly add the Guinness and 1 cup water, small bits at a time in alternation, stirring after each addition. (The Guinness will get all bubbly, so you don't want to add in too much at once.) Then, add the onion and mushroom mix to the sauce (which should at this point be delighting your nostrils with the decadent smell of beer and butter) and stir, adding in salt and pepper to taste.
This filling can also be made to include other vegetables (peas and carrots are common), as well as meat. If I'd had it, I probably would have thrown in ground beef or chunks of sausage at the mushroom phase. No such provisions were in my freezer at the time, unfortunately, but I'm sure they'd be delicious for you!

Potato Topping
5 or 6 large potatoes, washed and chopped into large chunks
3 tbsp butter
3 tbsp cream
4 cloves garlic, chopped
1/2 tsp nutmeg
Salt and pepper to taste
1/2 cup grated cheese (I used mozzarella and cheddar.)

Preheat oven to 350 F.
Boil potatoes in saucepan of water for about 15 minutes, or until tender. You should be able to poke a fork into a potato chunk and have it split in two. Drain almost all the water from the potatoes, but feel free to keep a little bit. Mash those spuds up with the butter and cream, adding in the garlic, nutmeg, salt, and pepper until the potatoes have reached (almost) optimum deliciousness.
Grease the bottom of a medium casserole dish. Layer in the Guinness-mushroom mixture, then spoon the potatoes on top in heaps, patting down to form a solid layer over the top. Sprinkle cheese over the whole thing, and toss into the oven for about 30 minutes, or until you're too hungry to wait anymore.
DEVOUR, while drinking the leftover Guinness.