My favourite venison casserole recipe is:
Dust venison in seasoned gluten free flour, sear on a very high heat until browned all over. Remove from pan and set aside.
Add a touch of oil to the pan and in with some smoked bacon lardons. Fry until crisp and the fat has rendered out and then add 4/5 finely chopped shallots (banana ones) or baby pearl onions, sauté until they are starting to soften add in whole baby mushrooms and a big splodge of tomato purée. Cook down for around 10 mins or so until the purée is rust coloured.
(Now I would add red wine and cook off but you can leave this out)
Back in with the venison, and then some really good beef stock - fresh if possible or at a push the stock jellies aren’t too bad (check they’re gluten free) It depends on how much you’re making to how much you add in but it should be quite liquid.
Lid on, but leave it cracked slightly to let steam out and into a really low oven, around 150 - 160 for 3-4 hours. It needs to be really low as venison is so lean it can become stringy very easily. Check it after 3 hours, pop it back in for longer if it’s not super tender.
It’s really simple and delicious, the veg is best served on the side rather than in it as the long cooking time tends to turn them to mush. It freezes and reheats beautifully!