I have to bake a giant cupcake tonight for a wedding and cover it in fondant. I've heard it's best to cover the base upside down to the bottom of the cake first, and then down the sides so the top is not covered, as it will be covered by the top of the cupcake. My main concern is how do I flip the giant cupcake base so it's sitting properly after I cover it? I don't want to make any dents or marks in the cake after it's covered.

Also, if I use the WASC recipe or this one here http://cakecentral.com/recipes/1972/durable-cake-for-3d-and-wedding-cakes how long should I adjust my cooking time for such a deep cake?

What I would do is put a large cardboard base underneath the cupcake, cover it (leave some fondant hanging to then tuck it on the top so it doesn't slide down) and then once you cover it, put another cardboard on the covered top (that is really the bottom), then carefully get a wide spatula, or better yet one of those pizza shovels or something flat and slide it underneath the cardboard and grabbing the top cardboard flip it over....am I clear?

Do not know how to adjust the time, but i will definetely bake at 325 to begin with.

I think I understand what you need...I would have a cardboard round or a wax paper covered pizza pan (I use those a lot for my layers) under the top (that will actually be in the bottom while you cover with fondant), after covering you can handle the bottom of the cupcake since it won't be seen and slide and put your hand under the pizza pan or cardboard round and flip, you won't have to touch the sides.
Regarding the deep pan, didn't it come with a heating core? kinda like the wonder mold for Barbie cakes? If it didn't you will have to bake at low temp (325) for longer time and keep and eye on it. HTH!

Is this the Wilton or Williams-Sonoma giant cupcake? If so, start your timer at 20 min. and then check on it. It'll probably need to go a little longer, but just keep an eye on it.

One other good way to cover the bottom is to do a chocolate shell. Very easy and gives fantastic results.

It's the Wilton pan, but since I'm going to use the WASC recipe and since the base is so deep I think it will nbeed much longer than 20 mins to cook. I've been told closer to an hour - is that right?

As for covering it with MMF do you think it might be best to cover the base right side up and not bother covering the bottom of it since the bottom will be on the cake board? Is that the best thing to do?

I always use the WASC. Depending on your oven, an hour could be too long. I always feel that it's better to estimate short, check it, and adjust accordingly. I've made it several times and don't remember it ever taking an hour to bake. But, that could just be my oven.

I would cover the cake just like a regular cake and not bother about doing it upside down.

One other good way to cover the bottom is to do a chocolate shell. Very easy and gives fantastic results.

Sorry I am very new to cake making. How would you make a chocolate shell? Thanks!

http://ohsugarcakes.blogspot.com/2009/03/candy-liner-for-giant-cupcake.html

This gives pretty good directions. I use a pastry brush to apply the chocolate to the pan. Also, I use the cake baked in the bottom mold. Just trim up the sides and smooth a little icing onto the inside of the shell. Slips right in.