I would use this special insulating fabric called InsulBrite, it is sold by the yard at JoAnnes and at Walmart, if the one near you still sells fabric. I have made many potholder hot pad fabric trivets and have even sold them on Ebay. I use pre-quilted plain color fabric, for the extra batting and plain color, that's the bottom piece.
The middle is a piece of Insulbrite, with the shiny side facing the 100% cotton print fabric you are using, which is the top layer. Only 3 pieces ready to quilt together for a potholder. Then seam binding all the way around and a small loop for hanging, and you are done in about an hour. from Deborah, Phoenix, AZ