Make your biscuits by whisking together, flour, and garlic powder. Add Greek yogurt, cold cubed butter and ½ cup of cheese. Mix well until a dough begins to form. Divide the dough into about 6-8 small balls. Set aside.

Preheat the oven to 400 F and prepare a 13x9 inch casserole dish.

In a large pan over medium-high heat ,add butter. Gently stir until the butter melts. Once melted, add onions and garlic and cook until fragrant and onions begin to turn translucent (about 5 minutes).

To the pan, add frozen vegetables, diced cauliflower, garlic powder, onion powder, salt, pepper and dijon mustard. Stir well. Cook for about 7-10 minutes until the cauliflower begins to soften. Reduce the heat to low, and sprinkle the flour over the vegetables, stirring as you sprinkle to ensure everything is lightly coated and large clumps do not form.

While stirring, add the milk and chicken broth- continuously stirring to ensure the liquid does not separate. Once added, cook with the lid off on low temperature for about 10 minutes, stirring periodically to thicken the liquid. Once thickened-stir in the cooked chicken and fresh thyme.

To assemble your casserole, add the filling to the 13x9 inch baking dish. Flatten each of the biscuits gently using your hands until they are about ½ inch thick round discs. Top the casserole with the biscuits (I like to use any remaining dough to fill in large gaps). Brush each biscuit with melted butter and top with remaining ½ cup cheese. Bake uncovered for about 30 minutes until the biscuits turn slightly golden brown and the filling is bubbling.