I think the secret to this easy recipe is the caramelized onions. When I caramelize onions I always do a lot extra because you can freeze them. Caramelizing onions by slowly cooking them in a little olive oil until they are richly browned makes the result intensely and wonderfully flavorful. If you've never done it here is a great video on the process. http://simplyrecipes.com/recipes/how_to_caramelize_onions/
*Caramelized onions (3 or 4 large yellow onions)
pork loin (whatever size you need or fits your cooker)
1 pkg dried onion soup (like Liptons)
2 cups sliced fresh mushrooms.
Slice and slowly caramelize onions in 2 T olive oil over medium heat, stirring often. Allow plenty of onions as they shrink as they cook and remember they can burn easily at the end of the process so watch closely as they start to brown.
Put caramelized onions in the bottom of the crock pot, lay the pork loin on top. Sprinkle with onion soup mix and mushroom... Cover and cook on low for 6-7 hours... I add no liquid because juices from onions and meat are sufficient... Sometimes I brown the loin first...... I serve it over thick homemade style egg noodles "Country Pasta" available at WalMart. Once it's in the pot spend the day stitching or shopping for stash......
*You can caramelize any type of onion, but depending on their sugar content, some might caramelize more quickly than others. A standard yellow onion is just fine--it actually contains more sugars than "sweet" onions. Caramelized onions are terrific served as a garnish in soups, on sandwiches,on pizza, in omelettes, and in the middle of grilled cheese sandwiches
TIP: Put a burning candle or two next to where you are chopping onions and it will help with the onions fumes...