I've been messing around with pesto sauce all summer long, starting with the classic version, and then following with some variations, like a simple tarragon pesto, and a bright, fresh rendition made with mint, pistachios, and feta. Well, this past weekend I was at the farmers market and saw some nice looking bulbs of fennel, fronds and all, and it struck me that I could make a pretty nice pesto out of them.
Like all the pesto recipes I shared before this one, my plan was to keep this simple: I was going to puree the fennel bulbs and fronds with oil, garlic, and nuts—in this case almonds (though walnuts or pistachios would be great here too). But as I was cutting up the fennel, and thinking about how fibrous and also watery it is, I decided to roast it first.
Cut into small pieces, the fennel roasts fairly quickly, so it doesn't add too much time to the recipe. Plus, you can toast the almonds while you're at it. When I tested my classic pesto, I found that toasting the pine nuts first didn't make much difference in the final flavor of the sauce. Here, though, the toasted almonds help underscore that deep, rich roasted-fennel flavor.
I also departed from my classic pesto recipe here by using a blender. I absolutely loved the taste and texture of classic pesto when made with a mortar and pestle, but tougher foods, like roasted fennel and almonds, are a little harder to work into a paste that way. The blender makes quick and thorough work of it.
By using raw fronds in addition to the roasted bulbs, there's still plenty of fresh fennel flavor in the sauce. The result is a more complex pesto that's just crying to be drizzled on tomatoes or grilled fish or eaten on hunks of fresh bread. Or, you know, pretty much anything else you can think up.