Place a small amount of water in an appropriate sized sauce pot. Place a steamer basket in the pot over the water. Bring the water to a boil while prepping the broccoli.

Rinse the broccoli well under cool running water. Divide the broccoli heads into florets. If desired, using a vegetable peeler remove the woody outer portion of the broccoli stalks. Cut stalks to desired size.

When the water is boiling, place the broccoli in the steamer basket, lightly salt if desired, and cover with tight fitting lid. Steam until broccoli is slightly past crisp-tender and still bright green in color.

Lower the heat to medium and melt the butter in the pan.

Sprinkle the flour over the melted butter and whisk together until smooth. Cook until bubbly.

Lower the heat to low and whisk in the salt, dry mustard, and a dash of white pepper.

Whisk in the milk until mixture is smooth. Cook and stir until bubbly and sauce thickens. If sauce is too thick, add a little more milk. If too thin, cook over low heat until reduced to desired thickness.

Turn off heat. Stir in the shredded cheese until cheese has melted and sauce is smooth. Pour sauce over broccoli. Sprinkle with crumbled/chopped pancetta. Serve immediately.