Leftover roast beef

[Smallstuff]

I have a mound of left over roast beef enough for two meals.
Today I need something I can leave in oven on auto while we are out. I was thinking of a stew. On line the recipes are all American and involve things like beef broth etc which I don't have!
Do you think I could just shove the beef in a casserole dish with a sliced onion, sliced carrots and mushrooms and some gravy granules and water ( I don't have any oxo cubes)......
If that sounds ok how long do you think it would need...I have only cooked stew with raw beef before which I cook slowly and on a low heat but don't want the cooked beef to dry out. Any ideas?
And does anyone have a pie recipe to use for tomorrow?
Ta

I would imagine you could do this fine, but as the beef is cooked already it only needs time to cook the veg so my guess would be 40 mins in a medium oven, and make sure it is wet enough to actually cook the veg and keep the beef juicy.

I used my leftover beef mountain in a cottage pie (magimixed the leftover beef; fried off onions garlic and carrots, added the beef leftover gravy some beef stock mustard tomato puree, topped with potatoes sliced in the magimix(guess what I got for Christmas). Baked for about 45 mins.

And the rest went in a risotto.

Thanks I thought about 45 mins at 180 it's in and I also added potato!! Unfortunately I don't have a mincing function on my Braun food processor so anything with mince is out!!, I need an old fashioned minced like my mum used to have that screwed onto the edge of the table!!,

I might leave the beef out of the stew to avoid it drying out, then just add it at the end on the stove.

How about some sort of pilaf? Fry onions and garlic, then add herbs/spices and rice for a moment, then stock/water/wine?, cover and cook. Add beef towards the end along with peas or other quick cooking veg/already cooked veg, to heat through.

I need an old fashioned minced like my mum used to have that screwed onto the edge of the table!!

Indeed - I have one, its very good for mincing cooked beef without totally shredding it.

I use leftover beef in either cottage pie or a meat sauce to go on pasta or in a lasagne.

thanks all....the stew was lovely....and DH whipped up a fab curry involving onion, garlic, apples, tomatoes and raisins and some chicken stock I found in the freezer!! Te pilar sounds good too so will keep that up my sleeve for next time!
Grimma where did you get your minced from??