01 - Bring a large pot of salted water to a rolling boil. Add the trimmed and halved Brussels sprouts, cooking for 4 to 5 minutes until just tender. Drain thoroughly and set aside.
02 - In a large skillet set over medium heat, melt the butter. Add the finely chopped shallot and sauté for about 2 minutes until soft and fragrant.
03 - Add the blanched Brussels sprouts to the skillet and sauté for 3 to 4 minutes, tossing occasionally, until they develop light golden-brown edges.
04 - Pour in the broth and let it simmer for 1 minute. Reduce the heat to low and add the Boursin cheese. Stir continuously until the cheese is completely melted and forms a creamy coating over the sprouts.
05 - Season with salt and freshly ground black pepper to taste. Remove the skillet from heat.
06 - Transfer to a warm serving dish. Sprinkle with chopped fresh parsley and lemon zest, if desired. Serve immediately while hot.