Crumble cubes into boiling water, mix to dissolve. Melt butter in a saucepan over medium heat. Add flour, onion powder and pepper. Mix into butter with a wooden spoon or whisk. While stirring, slowly pour in half the liquid. Once incorporated into the flour butter roux (it will thicken quickly), add remaining liquid and mix. Stir for 1and 1/2 – 2 minutes until it thickens to a gravy consistency (it's quick as water is already hot). Taste, add more salt and pepper if needed. Serve over chops, steak, sausages, veggies, roast chicken, pork, beef, lamb.