Bell Peppers Stuffed With Tomatoes

Oven: 350 deg F/180 deg Celsius.
(I find the above simple flavours quite adequate, but feel free to add fresh, chopped herbs such as thyme and rosemary).
Wash and dry, then slice the stem tops off the peppers. Remove the seeds and as much of the ribs as possible. (Use nice large peppers).
(*Do make sure the peppers will stand upright on their bottoms. These are not always even, so you might need to slice off a tiny bit here and there to make them stay upright. Try not to slice through the flesh!).
Season very lightly inside with salt and pepper (capers are salty, so don't season if uncertain).
Peel the tomatoes as thinly as possible.
Put a tablespoon of capers and a tablespoon chopped onion into each pepper cavity, and pop a peeled tomato into each one.
Add a tiny pinch salt and pepper to each tomato top, and sprinkle over each a 1/2 teaspoon sugar. (This is important for flavour -- do not leave out).
Dribble a tablespoon (or less) olive oil over each stuffed pepper.
Fit the stuffed peppers into a smallish oven dish so they stand close together and can't fall over. Add a tiny bit of water to the dish (they'll shed their own liquid anyway).
Otherwise, bake alongside a roast, with other roasting vegetables. If doing this, remember that a lemon juice-honey-mustard dressing is great on roasting veggies, and will complement the flavour of the stuffed peppers.
Roasting time: about 1 hour. Don't bake until the peppers collapse.