On a dutch oven, add butter and allow to melt over MEDIUM HIGH HEAT.
Then add chopped onions and saute' until it is soft and translucent for 2 minutes.
Add all purpose flour and cook until the flour becomes a light brown roux.
Add 2 cups of whole milk and whisk and stir until the sauce thickens.
Add dijon mustard or yellow mustard powder, ground white pepper, kosher salt, and hot sauce. Stir until combined.
Then add 1.5 cups shredded cheddar cheese and stir until the cheese is melted.
If you want to remain the little chemicals, don’t add the Velveeta. But I suggest you to add it for a distinct cheddar cheesy flavor and thickened soup.
Stir until it comes together.
Add the broccoli florets and the roughly chopped matchstick carrots to the cheese sauce. And stir.
Add the 2 cups chicken broth until it becomes a thick soup.
Add ½ cup heavy cream to it. Stir until rich and creamy.
Serve the soup warm with a sourdough bread bowl, slices of baguette.