Softening onions already in a dish

October 12, 2018 4:11 PM

I am making turkey shepherd’s pie. Though I cooked the diced onions at a low heat for 15+ minutes before adding the other ingredients, they still taste crunchy in the filling (which includes ground turkey, corn, peas, carrots and mushrooms). I have not yet added the mashed potato topping. How do I get the onions to become soft before putting the dish in the oven?
posted by lieber hair to Food & Drink (8 answers total)

Won’t they soften while they cook?
posted by suncages at 4:25 PM on October 12, 2018 [1 favorite]

Best answer: You could try gently simmering the filling in a pan with a lid with a wee bit of extra stock or liquid for five or ten minutes, but you'd risk mushy peas and carrots. Unless they're super-crunchy, maybe risk it and just bake as normal?
posted by halation at 4:26 PM on October 12, 2018 [2 favorites]

Response by poster: They don’t soften in the oven. I know because I’ve made this goof a couple times before. Right now I’m just sautéing the base mix at a low heat for a prolonged period. Hoping that does the trick.
posted by lieber hair at 4:27 PM on October 12, 2018

You could also microwave the whole mess on 30-40% power for 2-10 minutes, stirring every few minutes.
But that also risks overcooking the rest.

I think you’re fine to proceed as normal, unless someone has a very strong opinion or reaction to onions that are not 100% soft.

Seeing your update: you can cook at a lower temp for 10 min before turning up, or turn the temp down at the end for an additional few minutes, or turn the oven off but leave the pie in until it’s ready to serve. I use that last bit a lot, I especially love how almost all cookbooks treat it as heresy but it works great for me when used judiciously.
posted by SaltySalticid at 4:28 PM on October 12, 2018 [1 favorite]

I’m amazed they didn’t soften after 15 minutes cooking. I’d just cook the dish as-is. The onions should soften during the cooking.
posted by Thorzdad at 4:29 PM on October 12, 2018 [1 favorite]

Response by poster: I cooked it on low with a tiny bit of extra stock for another 45 minutes, and it became DELICIOUS. The mushrooms cooked way down and ended up giving everything an amazing umami flavor. And not a crunchy onion bit to be found!
posted by lieber hair at 6:07 PM on October 12, 2018 [28 favorites]

Recipes suggest that onions can be cooked to golden in 5 minutes. I like to leave them on low for up to 30 minutes, stirring fairly often, so that they begin to caramelize and are golden. You can go a bit faster with higher heat. Your dish sounds delish.
posted by theora55 at 7:35 PM on October 12, 2018 [5 favorites]

Layers of Deceit: Why do recipe writers lie and lie and lie about how long it takes to caramelize onions?

I also remember learning that a pinch of baking soda helps. 10 minute caramelized onions recipe
posted by Pig Tail Orchestra at 6:47 AM on October 13, 2018 [5 favorites]