Looking to prepare edible cannabis concoction

[Digemlo]

Hello there,
A buddy of mine is soon planning on tripping in a room alone for a day. He told me that he finds that due to weed's memory-inhibiting features (this could also be described as "a scattering of consciousness" or a loss of focus), he would like to somehow be high for this experience, but he will not be able to smoke whatsoever. He said he was thinking of doing one of the following things:
-brownies/cookies
-some sort of "tea" (boiling in milk)
-pre-made Leary biscuit (afraid to do so because his past experiences with this have failed)
-???

Anyways, he's looking for suggestions all around. Whatever he makes, it will have to be made the night before--which raises the question, if he boiled it in milk, would the cannabinoids remain active if he refridgerated the mixture?

Cookies/brownies would be nice, but he wasn't planning on using more than a ~1.75 grams if possible.

Any suggestions would be highly appreciated. Thanks!