Preheat the oven to 375°F (190°C). Grease a 9x13-inch casserole dish with butter or avocado oil.

In a saucepan over medium heat, melt the butter. Add garlic and cook for 30 seconds until fragrant.

Whisk in the cream cheese until smooth and melty. Slowly add the heavy cream and chicken broth, whisking until the sauce is silky.

Stir in the Dijon, onion powder, lemon juice, 1/2 teaspoon salt, and 1/4 teaspoon pepper. Simmer 2–3 minutes to thicken slightly.

Remove from heat and stir in half of the shredded Swiss until melted. Taste and adjust seasoning.

In the prepared baking dish, spread the chicken in an even layer. Scatter chopped ham over the top.

Pour the cheese sauce evenly over the chicken and ham. Sprinkle the remaining Swiss over the sauce.

In a small bowl, mix almond flour, Parmesan, smoked paprika, a pinch of salt, and a few grinds of pepper. Drizzle in 1 tablespoon melted butter (optional) and stir until crumbly.

Sprinkle the topping over the casserole. Bake for 20–25 minutes, until bubbly around the edges and the top is golden.

Let rest 5–10 minutes so it sets. Garnish with chopped parsley and serve warm.