• Preheat oven to 375°F. Lightly spray a 9x13 casserole dish with cooking spray.
• Bring a large pot of well-salted water to a boil. Add broccoli florets and cook 2–3 minutes until bright green and just tender. Drain thoroughly and allow steam to evaporate by spreading on a paper towel lined tray. Excess moisture will thin the sauce.
  8 cups fresh broccoli florets
  
• In a saucepan over medium heat, melt 4 tablespoon salted butter. Whisk in flour and cook 1–2 minutes until smooth and lightly golden. This roux forms the base that thickens the sauce.
  4 tablespoon butter, ¼ cup all-purpose flour
  
• Slowly whisk in the warmed milk and chicken broth, adding gradually while whisking continuously to keep smooth. Continue cooking, whisking often, until thickened enough to coat the back of a spoon, about 4-6 minutes.
  2 cups whole milk, 1 cup chicken broth
  
• Reduce heat to low. Add cubed cream cheese and stir until completely melted and smooth.
  4 oz cream cheese
• Stir in Lawry’s Seasoned Salt, freshly cracked pepper, dry mustard, onion powder, and garlic powder. Remove from heat.
  1 teaspoon Lawry’s Seasoned Salt, ½ teaspoon freshly cracked black pepper, ½ teaspoon dry mustard, ½ teaspoon onion powder, ¼ teaspoon garlic powder
• Gradually add shredded cheddar, stirring until fully melted and silky. Do not allow the sauce to boil once cheese is added, as high heat can cause separation and graininess.
  8 oz sharp white cheddar cheese
• Spread drained broccoli evenly in prepared casserole dish. Pour cheese sauce evenly over the top.
  
• In a small bowl, combine panko with 3 tablespoon melted butter and sprinkle evenly over casserole.
  1 cup panko breadcrumbs, 3 tablespoon salted butter
  
• Bake uncovered 30-35 minutes until bubbling around edges and golden brown on top. Optionally, broil for a couple of minutes for better browning.
  
• Let rest 10 minutes before serving to let the cheese sauce cool and thicken.

Making Ahead

• This casserole can be assembled ahead of time through step 8, without baking, covered tightly, and refrigerated up to 24 hours. Add the panko topping just before baking.