Melt the butter in a medium saucepan on medium.
Once melted, add the flour and make a rue.
Slowly add the milk and whisk continuously until combined.
Add all spices and onion.
Once it thickens, add the shredded cheddar and continue whisking until it makes a velvety cheese sauce.
Meanwhile, either cut the frozen broccoli pieces by hand to SMALL pieces/florets or throw it in the blender or food processor to chop.
Add the chopped broccoli and cooked rice to the cheese sauce.
TASTE for seasoning - then spread in a 9 x 9 glass baking dish.
Bake for 30 mins @ 350°F.