A large juicy hamburger topped with caramelized onions and mushrooms; threads of sweet, golden onions interweaving delicate strands of pasta under chunks of Italian sausage and al dente vegetables; a comforting bowl of French onion soup hidden beneath cheese-encrusted sourdough toast. Delicious, mouth-watering visions of amazing transformations a big bag of onions can take. So easy, and so inexpensive!
Slice a large quantity of onions. (You can do this with only one or two, but why? Leftover caramelized onions improve with a few days rest in the fridge. And those stragglers added to leftovers create interesting meals in minutes.)
Select a large, heavy pot. (Or any you can locate. But a large pot will hold all those onions, and a heavy one will hold the heat better.) Adjust the stove burner to medium-low. (If using a heavy pot, as suggested, low heat setting may suffice. Slow, steady heat cooks more efficiently and caramelizes onions with less chance of burning.)
Drizzle oil over onions in that pot. (Use a teaspoons olive oil for each cup onions, or vary type and amount, as desired. As long as onion slices all become coated, it's a matter of individual preference. Fixing food to your tastes is an advantage of being the cook!)
Select a long-handled wooden spoon; stir until onions are uniformly coated with oil. (A long handle is useful when reaching into a large pot; it keeps hands further from heat. I prefer a wooden spoon: it's nonreactive, unlike metal ones. A heat-resistant spatula also works well.)
Stir in salt, pepper, other spices. (Again, it's the cook's prerogative. Consider what spices agree with foods using these caramelized onions, and with people eating them. To accommodate recipes or dietary restrictions, add spices later.)
Cook slowly, stirring occasionally. (Patience: "Rushing it" with high heat will only yield disappointment. At worst it might burn, at best it won't be as sweet or flavorful.) Caramelization is a chemical reaction, requiring a series of events. Heat and time in proper proportions transform starches within onion to sugars. As moisture in fresh onion juices evaporates, sugars condense. Continued heat acts upon these sugars, further transforming through carmelization. Chemical bonds reorganize. (Similar to how crystalline table sugar melts, then darkens with slow heating to create caramelized dessert topping.)
Stir occasionally, but not constantly at first. (Benign neglect, a useful gardening principle with plants eschewing over-tending, may be applicable. Do something else in the kitchen. Intermittently return and stir during this initial heating.)
Stir frequently towards the end. (Attentive observation replaces benign neglect.) As appearance changes dramatically, deflating to less volume, stir more. (Decreased volume signals that juices evaporated, sugars become concentrated as starches convert to sugars.) Onions turn golden. Aroma changes: less "onion", more sweet.
Caramelizing onions turn progressively darker and stickier. (Attention is critical now.) Onions pieces clump as sugars caramelize. Definite resistance to stirring signals they are ready to enjoy. You can hasten the end process: Add a few drops of balsamic vinegar as onions are darkening and sweetening. A combination of vinegar and Worcestershire also works. Cook, stirring until vinegar aroma dissipates, at least 30 to 45 seconds. Use or refrigerate. Or do both.
You can proceed to French onion soup with what remains in your large pot. Sprinkle flour (a tablespoon for three to four onions), stir to blend over medium-low heat. After one minute stir in pepper, garlic, spices desired. Pour in beef broth. Heat 15 to 20 minutes. Meanwhile toast sourdough bread, place in oven proof bowls. Top with soup and shredded cheese. Melt cheese, then serve.
Caramelized onions flavors meld wonderfully with a wide array of foods. Beyond hamburgers, barbecue pork or grilled Portobello mushroom sandwiches improve with caramelized onions.
Enjoy meat entries ranging from steak (caramelized onions with bleu cheese) to pork chops (caramelized onions with apple and cranberries) to meatloaf (stuffed with caramelized onion, spinach, and feta). Add caramelized onions to mashed potatoes, pasta dishes, and soups. Or...