Reddit mentions of Roasted: A Homebrewer's Guide to Home Roasting Grain

I found this helpful:
https://www.amazon.com/Roasted-Homebrewers-Guide-Roasting-Grain-ebook/dp/B00BGHU5JC

I've done a couple batches of pale gold, gold, and amber. I really like the pale gold and gold. Vaguely similar to Vienna malt.

You need to moisten and sprout the grains for a particular length of time- too short and your malt will be enzymatically poor, and you'll need extra mashing steps to break down protein; too high, and you'll get seedlings instead of malt.

Then there's drying- it's very easy to overkiln your malt and make malt that's too dark, or underkiln and not dry in enough. Or you can kiln inconsistently- some may be too dark, some may be too light. This after taking the time to harvest all that grain.

All this inconsistency means your beers are inconsistent- you have no idea how they will turn out, even with the same recipe. That's fairly troubling.

These are things that commercial malt producers, with their industrial machinery, perfectly controlled processes, and hundreds of years of experience, have perfected. And they can get you wonderfully consistent malt for less than $40 for a 50-55 lb bag. If you want to give it a go and experiment, who am I to stop you? I welcome the voice and experience of someone who does their own malting- not many do their own. However, sometimes, some things are better left to the pros.

However, home-toasting commercial malt is easy, quick, and I'm told contributes greatly to flavor. There's little issue with consistency, since you're usually talking a couple pounds or less per batch. There are some books out there like The Homebrewer's Garden and Roasted, which comes from this great blog post