PARTIAL MASH METHOD #1
This method is specific to recipes with 2.5 lbs of grains or less.
1. Place grains in grain bag.
2. Put into pot with 3 gallons of water and turn on the heat, raise the temperature to between 151° and 158° depending on the recipe.
3. Turn off the heat and place a lid on the pot. Place a heavy towel over the pot and let stand for 40 minutes. DO NOT CHECK CONTENTS FOR FULL 40 MINUTES to avoid releasing heat from the pot.
4. After 40 minutes, open pot and slowly dip grain bag in and out of pot 7 to 10 times slowly. Throw grains away.
TIP: DO NOT squeeze juice out of bag as this would release tannin, causing an astringent characteristic to the beer.
PARTIAL MASH METHOD #2
This method is for when the recipe calls for 2.5 to 5 lbs of grain and requires a metal (NOT PLASTIC) spaghetti colander.
1. In a separate pot from your regular brewing pot (2 to 3 gallon capacity), place 1.5 gallons of water and raise the temperature to 158° to 160°.
2. Place LOOSE grains in the water (no bag).
3. Place lid on pot and cover with towel and leave for 45 minutes.
4. Place colander in regular brewing pot. Colander should catch on the handles and be suspended on the pot. Dump loose grains from first pot into colander.
Note: Grains will be left in colander and sweet wort will fall into pot.
5. Rinse out 1st pot and place 1.5 gallons of water in pot and raise temperature to 180°.
Tip: Start out with hot water from the tap in the interest of saving time.
6. With pyrex measuring cup or ladle, slowly drizzle this water over grains in colander.
Note: This is the lautering process, commonly called sparging, which rinses the remaining sugars from the grain bed.
7. Remove colander with grains and feed to the pigs or place on a compost pile.
As you can see this process is ridiculously simple, so resist the temptation to make it complicated.
Note: What you have just done is exactly the same process as an all grain brew except that you do not need larger vessels to contain the grains..
8. From this point on continue as in any regular extract batch, bringing your wort up to a boil and adding your grains. IT IS IMPORTANT TO TURN OFF FIRE WHEN ADDING EXTRACT.