Garlicky Pot Roast

1. 1Cut off the very top (the nonroot end) of the garlic heads. Discard the tops. Place the garlic on a large piece of aluminum foil. Drizzle with the olive oil.
2. 2Fold the foil into a large package, sealing the edges well. Place the package in the slow cooker. Cover and cook on low for 8 hours.
3. 3Set aside 1 whole head for the pot roast sauce. Transfer the remaining 7 heads to a jar or freezer container and cover the surface of the garlic with about 1/2 inch of olive oil. Cover tightly and store.

Marinate the roast:

1. 1In a bowl large enough to hold the roast, stir together the chopped garlic, brown sugar, olive oil, vinegar, tomato paste, and 1 tablespoon each of salt and pepper. Add the roast and turn it to coat on all sides. Cover the bowl and marinate for at least 3 hours, or overnight in the refrigerator.
2. 2Place a large frying pan over medium heat. Lightly coat the bottom of the pan with olive oil. Remove the roast from the marinade and pat dry. Discard the marinade. Lightly season the roast with salt and pepper. Brown the meat on all sides, about 7 minutes per side. Set aside the roast, but do not clean the pan.
3. 3Preheat a 6-1/2-quart slow cooker to high.

Make the sauce:

1. 1Add the onions to the reserved frying pan and cook until brown, 3 to 5 minutes. Add the chopped garlic and cook for 2 to 3 minutes more, until the garlic is very fragrant and has softened slightly; do not let the garlic brown. Add the beer. Scrape up the browned bits with a wooden spoon or spatula. Transfer the mixture to the slow cooker insert.
2. 2Place the roast and any collected juices in the insert. Squeeze the head of roasted garlic out of the skin and into the insert. Add the stock, gingersnaps, and tomato paste. Stir together. Cover and cook on high until the roast can be pierced easily with a fork, about 7 to 8 hours.
3. 3Remove the roast from the slow cooker and keep warm. Strain the sauce before serving. Cut the roast into large chunks and serve hot with your choice of accompaniment. Pass the sauce.