There are a few thoughts to how to add the pumpkin. Some roast it in the oven at around 350 for a while till it browns some, then add it to the mash. I, OTOH steep the pumpkin in my strike water for an hour in a BIAB type paint strainer bag, stir like crazy. I then steep my sparge water the same way while the mash is mashing. I also used to add my spice with 5 min left in the boil, but that gives you less control over the spice flavor. The other way is to take the pumpkin spice, like two TBSP, add it to three shots of dark rum, and let that sit in a tupperware for a few weeks before bottling day. On bottling day, slowly add the spiced rum (minus the actual spice) to the bottling bucket, tasting several times till you get just more than the right amount of flavor before you add your priming sugar. If you plan on letting your pumpkin beer sit for say... 6 months like I do, you want the spice to be somewhat prominent cause its gonna condition out. If you are gonna drink as soon as its carbed, then spice it till its just right and no more.
