Pumpkin Beer

Process:

Preheat oven to 375°F (190°C) while heating strike water
Prep pumpkin by removing and discarding the skin and seeds, and cubing the flesh into roughly one-inch (2.5 cm) cubes, and placing on a baking sheet
Mash at 156°F (69°C) for one hour
During mash, roast the pumpkin, 375°F (190°C) turning the cubes every 15 minutes, until browned, about 60 min
During mash, prepare a slurry of 1-2 tsp pumpkin spice, the brown sugar, and a little bit of water
Sparge and collect wort
(This will probably occur during the runoff:) toss the roasted pumpkin cubes in the spice-brown sugar slurry and roast at 375°F (190°C) for 10 more min
Add roasted, spiced pumpkin and hops at start of boil
Add spice blend at flameout
Pitching temp and fermentation temp schedule not provided - stay in ideal range for your yeast strain
Key step: add 2.5 lbs of roasted, caramelized pumpkin (see below) -- leave beer on pumpkin for one week (note from anonymous author: I feel this is the step that really puts the 'true' pumpkin flavor into my beer; along with discovering biscuit malt in 1995, I credit it as turning a good pumpkin ale into a great one. This is also where you use the molasses and maple syrup mentioned in the ingredients; toss them into a hot pan with your roasted pumpkin to candy. You can skip the secondary (or split off a gallon or two to try it on a smaller scale) if you find it unconvincing.
Roasted, caramelized pumpkin recipe (late addition to fermentor)
(You can either prepare this ingredient on brew day and freeze for later use, or reserve the cut, raw pumpkin in the freezer and make this on the day you will use it in the fermentor)

2.5 lbs (1.13 kg) pie pumpkin - post-fermentation (see below)
4 oz (118 ml) blackstrap molasses - post-fermentation (see below)
4 oz (118 ml) maple syrup - post-fermentation (see below)
Prepare pumpkin into roughly one-inch (2.5 cm) cubes and roast as per above
Saute the roasted pumpkin, blackstrap molasses, and maple syrup in a hot pan until the pumpkin is candied (the sugars are caramelized)
Use immediately or freeze for use when needed