SILIVOSilicone Muffin Pans Nonstick 12 Cup(2 Pack) - 2.5 inch Silicone Cupcake Pan - Silicone Baking Molds for Homemade Muffins, Cupcakes and Egg Bites - 12 Cup Muffin Tin

Q: Does this pan have a rigid metal frame to support it or must the pan be placed on a cookie sheet to stabilize?

There is no rigid frame and I would definitely put a pan or wire rack under them for support while moving them into and out of the oven

Q: How long and what temp for muffins and cupcakes? Brownies?

Generally 350° and I’d check after 8-10 minutes with a toothpick

Q: Is the size, top and bottom the same diameter? Some are quite different.

The top and the bottom are almost the same size. The Muffins come out kind of square.

Q: Do you have to spray these with cooking spray?

No, I actually do not have to spray them with Pam or anything like that if you’re making muffins I don’t believe you have to use anything either. We use them for making dog food meatloafs for our Labrador it’s better and easy to do this and healthier for him. We do not use cupcake Papers or anything like that we just put the meat vegetables, fruit etc. right in and it pops right out like a big healthy meatball. I’m sure if you’re using cake it would be absolutely no problem to do muffins. We love them it’s a matter fact we have enough to be able to make dinners and breakfast for 31 days. I hope this answers your question it’s a little more than you probably needed to know, but just wanted to pass it on. We love them best things we have a bike I just wish I could get them. Just a little bit bigger. Enjoy!