Steam bite sized cauliflower in small amount of water for about 5 minutes.
Remove from pan.
Melt butter, stir in flour and 1/2 and 1/2 and stir until thickened. ( if gets too thick, simply add more milk)
Add garlic, mustard, and onion flakes
Add finely chopped jalapeño
Stir in 1 cup of cheese
Add in cauliflower and stir.
Pour into an oven proof container, top with remaining 1/2 cup cheese and bake for 10 minutes.