How can we bake a sponge cake in a grill microwave oven where there no preheating functionality? It's an Electrolux grill microwave oven. Is there any substitution to the preheating process?
If you are sure that your oven can turn the microwaves completely off, then use it like any other toaster oven. Turn the microwaves off so only the heat elements are on, turn to the temperature you need, let it "bake" for 10 minutes without anything inside. It is preheated. Bake the cake as usual. Be aware that, if the heating elements are on top only, you probably won't get a good cake. Cakes can be made in toaster/grilling ovens, but need heat from both below and above, or in the worst case from below only.
If you don't have temperature controls for the grill, you can risk a try, but it is unlikely that the temperature will be suited for a cake.
If you can't turn off the microwave function (and sadly, there are even some ovens which have a button for it but still use microwaves when it is selected), there is no way you can bake cakes with it. You need another oven for any dough then, your options start with toaster ovens at ca. 50 Euros.
I have Electrolux grill microwave. But I can bake with this microwave its amazing I can make tandoori food soup boil reheat steam I can make pizza also with this microwave I can make cookies also with this microwave if you want to bake I think that I can help you if you want to make pizza press combi mode for 10 minutes if you want to bake cake the same thing you can do it for 25 to 30 minutes to make cookies press grill but don't use any grill tray place the Cookie dough on the microwave glass plate for15 minutes off the microwave turn the cookies and on microwave grill mode for 6-8 minutes and then on micro mode maximum for 1 minutes and cookies are ready if you want to want to preheated the oven you can press grill or micro mode