Heat a medium skillet over medium heat. Add 2 tablespoons butter and the 1/2 cup diced onion. Sauté, stirring occasionally, until the onion is soft and translucent (about 4–6 minutes).

Pour in 2 cups stock or broth (your choice of beef, chicken, turkey, or vegetable) and stir to combine. Add 1/4 cup heavy cream and stir until the mixture is warmed through.

Add 1 tablespoon cream cheese and whisk until the cream cheese melts and the mixture is smooth.

Remove the skillet from the heat and let the mixture cool for 1–2 minutes to reduce splattering. Transfer the mixture to a blender and pulse until smooth.

Return the blended gravy to the skillet over low heat. While whisking, slowly sprinkle in 1 teaspoon psyllium husk and continue whisking until the gravy reaches your desired thickness (psyllium thickens quickly).

Stir in 1 teaspoon Worcestershire sauce and the remaining 1 tablespoon butter until the butter is melted. Season with salt and pepper to taste and heat just until warmed through.

Remove from heat and serve.