Ditto spunbutterfly, but also know that steel-cut oats don't have to be slow-cooked. I make them all the time on the stove, and they take ~45 minutes or so. I like to just cook them straight and stir in canned pumpkin, cinnamon, and flax seed meal, then top with chopped walnuts and maple syrup.
Nuts totally help supply, in my experience. Hummus is also great because it has plenty of protein, fat, and the sesame and garbanzo beans are both lactogenic foods. I wish I could remember what I ate the day my pumped milk was basically the texture of heavy cream! The fat layer was so thick that it held the thinner milk back when I turned the bottle on its side.
Spun, not to get creepy, but do you work near the market? I'm about a block away and go there regularly. I'll have to check out the cookies you're talking about!
And this all reminds me that I've been meaning to make another batch of lactation cookies.