Caramelizing onions takes time, often much longer than a recipe cares to admit. I have never caramelized an onion in less than 30 minutes. Sweet onions are not better for caramelizing—their “sweet” label is not an indicator of more sugar but, actually, of more water, which dilutes the sulphuric compounds in onions, making them seem less harsh. When caramelizing onions, you have to cook out all of the water, then transform the sugars. More water in the onion just means it will take more time. Similarly, using the widest, shallowest, pan you have speeds up evaporation and, in turn, caramelization.
As onions caramelize, they will inevitably stick to the bottom of the pan. Enter the glory of deglazing—the process of adding a liquid to release those intensely flavored browned bits (aka fond) from the pan. Though this is traditionally done with wine, I like to use hard cider, whose apple flavor complements the onions. You can also use water if you don’t want to add a new flavor.
For all you planners: Caramelized onions freeze perfectly. I use 8-ounce deli containers for storage because they stack, and one cup is a good amount to have on hand at any given time—ready to be scattered on a pizza, or slices of buttered toast, or a billowy Dutch baby.
This oven-puffed pancake can host all sorts of toppings: I’ve topped it with roasted cherry tomatoes, garlic, and lemony mushrooms. Or a salad of raw asparagus, goat cheese, and dill. Sky’s the limit. This iteration combines the flavors of cozy French onion soup with the easy decadence of the Dutch baby. Serve alongside a big green salad. —abraberens
Test Kitchen Notes
In Eat Your Vegetables, chef, Ruffage cookbook author, and former farmer Abra Berens shares a seasonal recipe that puts vegetables front and center (where they should be!). Missed an installment? Head here to catch up. —The Editors
- Prep time 15 minutes
- Cook time 1 hour
- Serves 4
onions, thinly sliced
hard cider or white wine
sharp melty cheese, like Gruyère or white cheddar, grated
- In a large pan, heat a glug of neutral oil over medium heat until it shimmers. Briefly fry the thyme sprigs and caraway seeds until fragrant, about 30 seconds. Remove the thyme sprigs and save to garnish the Dutch baby after it is baked.
- Add the onions to the pan with a big pinch of salt and stir to coat. Cook over medium heat, stirring infrequently and lowering the heat if needed, until they are deeply caramelized, about 30 minutes.
- Add the hard cider to deglaze the pan and use a wooden spoon to release any caramelized bits that have stuck to the bottom. Keep cooking until the cider has completely evaporated, about 2 minutes.
- Heat the oven to 425°F. Place a large cast-iron skillet in the oven to heat up for 7 to 10 minutes.
- Meanwhile, whisk or blend the eggs, flour, milk, sugar, and a pinch of salt until smooth.
- With the pan still in the oven, add the butter, close the oven, and let the butter melt, being careful not to let it burn. When the butter is melted and foamy, pour in the batter.
- Bake until the pancake is puffed and the center is just cooked through, about 15 minutes.
- Remove from the oven and spoon the caramelized onions on top of the pancake. Top with the grated cheese and return to the oven to melt the cheese, 5 to 7 minutes.
- Remove from the oven, garnish with the fried thyme leaves, and cut into wedges. This is lovely alongside a big green salad.