Yes, one can cook brownies without an oven. They may be cooked in a microwave, on a barbecue, in an Easy-Bake oven, on a stove top. There are also no-bake brownies.
You can also cook brownies in a bread machine.
you don't
If Tommy has an oven then he can makes cookies, however without the use of the oven Tommy does not make cookies please refrain from making me so confused with you next question, you mental degenerate.
It can be, such as in the sentence, "I took out the cookies using an oven mitt."
You can bake without an oven by using alternative methods such as a stovetop, a microwave, a slow cooker, or a toaster oven. These methods can help you bake a variety of dishes like cakes, bread, and cookies.
No, cookies would not bake well on the barbecue.
Yes! Here is the recipe! (This is an Oven recipe!) Egg + Flour + Butter = Cookies! If you want to make chocolate cookies, this is the recipe! (This is also an Oven recipe!) Cookies + Chocolate = Chocolate Cookies!
Heat By heat
It's perfectly possible to bake cookies without an oven. You can use a microwave, stove or toaster oven; the cookies will have to be cooked in a different way though so you'll either need to use a certain technique and/or a recipe especially for baking cookies without an oven (there are plenty of those online, just search "no-bake cookies").
An oven
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No, the shape of a cookie sheet has nothing to do with cookies burning. How cookies burn in the oven is usually due to heat circulation in the oven, evenness of heat in the oven, or the position of the cookie sheet relative to the heat source.
It can be either. Leaving the cookies in the oven too long is the effect of forgetting that there are cookies baking. Leaving the cookies in the oven too long is also the cause of burnt cookies.