1. Trim the ends from the Brussel sprouts and remove and loose leaves.
2. In a large saucepan of boiling, salted water, cook Brussel sprouts for 10 - 12 minutes. Drain well.
3. In a medium-sized heavy-bottom saucepan, melt butter over medium heat.
4. Gradually whisk in flour, stirring constantly for 1 and 1/2 minutes.
5. Gradually whisk in milk, and continue to cook while whisking constantly.
6. Cook sauce for 5 minutes, stirring constantly.
7. Stir in honey-dijon mustard, salt and pepper.
8. Remove from heat and stir in 1/2 cup of the shredded cheddar cheese, then add in Brussel sprouts and combine.
9. Spoon into a greased 11 x 7-inch baking dish.
10. Top with remaining shredded cheddar cheese.
11. Bake in 375F oven for 25 minutes.