Oven – How long should I wait for the gas oven to heat up

This depends on a lot of things.

The idea of preheating is that you want to get all the surfaces inside your oven (walls, floor, door, racks) up to the desired cooking temperature. This makes for more even temperatures throughout the oven, and gives a little thermal mass so you don't lose ALL your heat when you open the door for a few seconds or put something cold in there.

Then there's the question of what you're putting in the oven. An aluminum sheet with a few room temperature cookies on it won't pull the temperature in the oven down like a 25 pound turkey that's 40F/5C inside. You want to be more careful to do a complete preheat if you're going to be soaking up a lot of your starting heat.

Our oven, which has a large baking stone in the bottom all the time, takes a while to get uniformly up to temperature, even after the oven says it's preheated, because the stone doesn't heat up as fast as the rest of the surfaces. It takes at least 20 minutes after the "I'm fully heated" beep before the stone is fully up to temp. We have problems with things baking poorly if we don't preheat for quite a while, but on the upside, if we put a cold roast in or open the door a lot, the temperature in the oven stays pretty high.

If your oven is lightweight, flimsy or drafty, it may be as hot as it's going to get the moment the preheat alert goes off.

45 minutes is probably a lot more preheat than you'll need in almost any case. In some cases even 15 minutes is more than you need. It really depends on your oven and what you're putting in.

I have used gas ovens with gas hobs, electric ovens with electric hobs, and electric ovens with gas hobs. By far the best combination is gas hob and electric oven. I'll break the pros and cons down:

Gas Hob

Pros:

• Heats up quickly
• Heat changes quickly - when you turn it off, it's off.
• Fine control over heat

Cons:

• Can create 'hotspots', but this is why you have different sized rings
• Can be fussier to clean
• Obvious danger of gas leaks, but modern safety systems mitigate this

Electric hobs are pretty much the opposite. They can be slow to heat and react slowly to heat changes (so if you want to go from a boil to a simmer you have to plan 20 minutes ahead). They also have the disadvantage of remaining hot even when they're turned off, which can be dangerous. Their only advantage over gas hobs is a more even heat across the pan, and being easier to clean.

Electric Oven (preferably fan)

Pros:

• Quick to preheat
• Even temperature throughout the oven
• Precise temperature control

Cons:

• None that I can think of

In contrast, gas ovens are slow to preheat, have marked zones of different heat (cooler at the bottom, hot at the top) and have coarser heat control. Also, because the flame is generally at the back of the oven, you can end up burning larger dishes that butt right up to it. All this builds up to make an unreliable oven (in terms of cooking results).

In conclusion, a gas hob/electric oven combo is the best because it gives you ultimate control over your cooking.