Mine didn't thicken up at all, so I put it on the stove and heated it up (stirring constantly) as you suggested. It was still runny, so I turned up the heat and added some cornstarch and it started turning into scrambled eggs (stop laughing everyone), so I threw it all in the blender and voila. . .it turned into a thick sauce LOL. I also added some herbes de provence (hey, why not). Served atop cooked cauliflower. Made for ZWT5.