Preheat the oven to 375°F. Place the cauliflower florets, olive oil, salt, and pepper in a 8×11 baking dish and toss to combine.,
STEP 2
Bake for 20-25 minutes, or until the cauliflower is tender and slightly browned. Set aside.,
STEP 3
In a large saucepan, melt the butter over medium heat. Whisk the cornstarch and water in a small bowl and gradually add it to the melted butter until combined.,
STEP 4
Gradually whisk in the milk. Continue to whisk until the mixture thickens and starts to bubble.,
STEP 5
Stir in the Dijon mustard, garlic powder, and paprika.,
STEP 6
Remove from heat and stir in the cheeses until they are completely melted and the sauce is smooth.,
STEP 7
Pour the cheese mixture over the baked cauliflower and stir to coat the florets evenly.,
STEP 8
Bake in the preheated oven for 20-25 minutes, or until the top is golden brown and bubbly.