It's not a traditional soubise since it uses bacon grease instead of butter, but it came out really good.
I used all scallions/green onions the first time I made this. The second time I used 1 bunch of scallions/green onions and a new/spring onion. We liked the all scallions recipe the best. It was a prettier shade of green as well. I don't know if I'll try the leek version or not given the new/spring onion results.
Serves 2 generously
4 slices thick cut bacon
1/2 pound scallions, spring onions or leeks
1/2 pound fennel bulb plus fronds for garnish
1/2 cup white wine
1/8 tsp baking soda
1/2 cup heavy cream
1/2 cup grated Parm R plus more for garnish
Salt and pepper
1/2 pound orecchiette
In a large straight sided skillet, render the bacon over medium low to medium heat. Remove bacon from pan. Pour grease out into a heat safe bowl and clean pan if needed (i.e. a lot of browning on bottom). Return grease to pan. Chop.bacon into small pieces, reserve.
Start pasta cooking per package directions. Cook until almost done. Drain, reserving 1 cup pasta water.
Meanwhile core fennel bulb and thinly slice. Thinly slice scallions/spring onions/leeks separating white and light green parts from the darker green parts.
Place the fennel and white and light green scallion/spring onion/leek parts in the pan with the bacon grease, add the white wine and some salt, and cook over medium to medium low heat for 5 minutes, stirring occasionally. You don't want any browning. Add the baking soda and cook for 8 minutes, again avoiding browning. Add the darker green parts, stir and cook for 3 minutes. Add the cream and let cook for 2 minutes until it thickens slightly. Let cool for a few minutes, then place in a blender and process at high speed until everything is pureed. Rinse skillet out then return pureed mixture to pan. Add the bacon, pasta and 1/4 cup pasta water to pan and stir over medium low to medium heat until well combined, about 2 minutes. Add additional pasta water if sauce is too thick. Add the cheese, stir, and add additional pasta water if needed. Add some freshly grated black pepper, stir. Divide pasta between 2 bowls, garnish with more Parm R and fennel fronds. Serve.