Over the years I have stepped up my fermenters to 55 gallon barrels (perfect for 40 gallon all grain mashes, which gives you (3) 15.5 keg charges with headroom). I was asked to share this recipe which I have done for the past 2 years, and brought to a couple gatherings. I will post both my full batch recipe, and a scaled down 5 gallon recipe.
When followed, this recipe has a great blend of the smoothness of wheat and the spiciness of the rye. The toasted oats, however, is what gives this bourbon a finishing flavor that to me is like drinking toasted marshmallows. I love my other bourbons like Honey Bear and my Chocolate Sundae, but this is my go to traditional bourbon, with the SCD flair

40 gallon Batch
50 lb Corn Meal
9 lbs Red Wheat Malt
9 lbs White Wheat Malt
9 lbs Rye Malt
3 lbs Toasted Oats*
* I have made this with several types of oats, but my best results were from rolled oats, that are the oat grain that is cracked from the feed store. You will get the same flavor profile if you just use Quaker Oats Oatmeal as well. I have done both. Toast the same regardless.
To toast the oats, spread the oats on a cookie sheet, and place in the oven at 300 degrees. Depending on the amount you toast, how thick you spread them, and your oven, times can vary. I think for 3 lbs, split between two sheets, I toasted for 1.5 hours (maybe a half hour if only doing 1/2 pound). Stir every 15 minutes. The important thing in the end is the color. You want them all to be golden brown and toasted. If you are a cook, you will know they are done by the smell of the kitchen. It is wonderful. This is one process that your SOH won’t mind. *
The process is the same as all my bourbons, and I follow my Large Batch Mashing process for this. You can also use enzymes, just adjust your process. I put the corn and toasted oats in the fermenter, and fill it up with 40 gallons of boiling water (the furious boil, not cute boil). Then I wrap it up with blankets, and let it naturally cool to 150 (overnight if needed). Then I add my Red, White, and Rye malts at 150, and let it sit for at least an hour or two, stirring a couple times. Should hit that SG of 1.06 or so. Then cool, and pitch a ¼ cup or whatever of bakers yeast.
5 Gallon Batch
7 lbs Corn meal
1 lb Red Wheat Malt
1 lb White Wheat Malt
1 lb Rye Malt
1/2 lb Toasted Oats
Put the corn and toasted oats into a 6 gallon bucket. Fill bucket up with boiling water. Wrap in blankets, stirring as frequent as you like. Mine takes about 3 or 4 hours this way to naturally hit mashing temp, so I stir 2 or 3 times during this time. When the mix hits 150, add your two wheat malts and Rye malt. Wrap up again, for a couple hours. When done, chill and pitch yeast.
This is definitely a great bourbon to age on new oak for 6 months to a year. The full flavor profile comes together in that time.
Enjoy!
-SCD