I've had brownies once, and cookies several times, and some drinks too.

I wouldn't do them so late at night as it takes a good hour or two for them to fully kick in.

My source gave me a x-mas treat brownie last year and I ate it at 11am, and I was stoned out of skull until 7pm. I smoked a joint with him as I ate it, so maybe smoke a little bit after you eat it. Or, smoke none at all and just get fried from the brownie.

Eating cannabis lasts much, much longer than smoking it, and I found that I didn't get that burnt out either, if that's a problem for you, so I suggest eating it at noon and being fried all day, or eat at supper time and be fried all night.

By the time it kicks in, it will be 2-3am and you plan to stay up late the next morning...? If so, go for it, but if you plan to pass out after only 4hrs after digesting it, just smoke it up instead.