I'm brewing a Stout that calls for the step.
7# UK Pale Ale Malt
2# Flaked Barley
1# Roasted Barley
Recipe calls for 15 min at 120F and 60 min at 150F ... Now I realize this can be mashed entirely at 150, but I want to follow the recipe and do the step. I mean we could argue all day about unmalted roasted barley and whether or not to 120 step it. This is a Jamil Zainasheff recipe and he contends the roasted barley should be crushed really fine, like in a coffee mill or use a rolling pin after a normal crush. According to Jamil to get the right color and bittersweet chocolate flavor this is the way to go.
I use Beersmith but I didn't realize I could use the step mash like that, duh... thanks HBH ... I was thinking it would have to be like Bobby_M said, start really thick and then thin with the right water to get you to 150F and 1.25Qt/LB consistency.
Edit: Beersmith has it under the double infusion category. For me it has me starting at .9qt/# and then after the additional H2O ending at 1.5qt/# ...