Cauliflower Gratin – Fustini's Oils & Vinegars

Ingredients

• 1 large head cauliflower, cut into florets
• 2 tablespoons Fustini's Herbs de Provence olive oil
• 1 teaspoon salt, divided
• 1 teaspoon pepper, divided
• 4 tablespoons butter, cubed
• 3 tablespoons all-purpose flour
• 2 cups 2% milk
• 1 cup shredded Swiss cheese
• 1/2 cup grated Parmesan cheese
• 1/2 teaspoon onion powder
• 1/2 teaspoon ground mustard
• 1/2 teaspoon Worcestershire sauce
• 1/8 teaspoon cayenne pepper
• chopped fresh thyme, optional