This Casserole Carrier will keep your dish safe and hand heat free. Food will stay warm just a little longer with the insolation provided. This one is a gift and I'm filling it with all the fixings for my favorite hot dip.
this project is based off the size of your particular casserole dish. The measurements will need to be filled in accordingly. These are guide lines intended to help you work through figuring out your own dimentions. they are by no means exact.

Step 1: What You Will Need

Main fabric less than 1 yard
Lining less than a yard
Isolated batting
Thread
Casserole dish with lid
Zipper (2 x width )+length + 3"
or zipper off the roll works well, less than a yard needed.
webbing yardage needed is (Width x 6") + (depth x 4") + 2" for join *a little extra is good.
Marking tool
Ruler
Sewing machine
Iron
Pins
Scissors

Step 2: Getting Started

You will need to take detailed measurements of the dish. Using the larges dimensions determine length, width, and depth of your dish with the lid on.
Cut 2 rectangles from main fabric using the measurements length + 2" by the width + 2".
Cut 2 long and thin rectangles the length of zipper +2 by depth + 1" from main fabric.
(There is a bit of wiggle room here. its very hard to get an exact on this before you sew.
Cut these 2 pieces next to each other so the repeat on the pattern looks better. )
Cut 1 rectangle length + 4" by the depth + 1 1/2" . You can cut a lining piece this same size at the same time.

Step 3: Cut Lining and Batting

ruff cut the lining and the batting 1/2" or larger all around

Step 4: Assembling

Layer the lining right side out then batting then fabric face up. Pin in place

Step 5: Baste

Stitch the layers together. You can use a regular long baste stitch or zig zag stitched. be sure to stay closes to the edge with stitching.
Trim batting and lining to match face fabric . this is much easier then keeping the layers straight and from shifting if all 3 were the same size.

Step 6: Zipper Time

Take the 2 long this rectangles and fold them in half log ways. you can press them if needed.
Baste close to the raw edge on the long side.
Pin fold to the zipper and one on the other side of the zipper. Give yourself some room. No need to be very close to the zipper here. Check the print to see if the design is lined up.
Stitch very evenly along the fold, then repeat for other side of the zipper.
Use a zipper foot if you need to.

Step 7: Baste Again

Take the small rectangle and baste it to the matching lining, right sides out for both fabrics.

Step 8: Attach to the Zipper Panel

Take the small rectangle and sew right sides together to the zipper panel as shown with 1/2" seam allowance

Step 9: Zipper Panel Attached to Top.

with right sides together pin zipper panel along the short side of the large batted rectangle otherwise known as the top of the carrier.
the seam you just made will be even with the long side of the rectangle. Sew in place using a 1/2" seam allowance. stop stitching and back-tack 1/2" from the end of the side indicated by the purple dot.

Step 10: Snip

Snip up to but not through the stitching.

Step 11: Turn the Corner

the snip you just made will help you to make a clean turn. pin the zipper panel down the next side. Start sewing at 1/2" down and in, or where you just stopped sewing previously. You will repeat the process to round the next corner as well.

Step 12: Making the Join

stop sewing 2" before the 3rd corner, indicated by the pin.
Take the unattached non-zippered part for the panel and pin it along the remaining long side towards the corner. pin along the short side at the corner. once you have determined where they should meet sew them together along this short side. Trim off any excess fabric to a 1/2" then you can continue to attach the zipper panel to the top.

Step 13: Time to Flip Over to the Other Side

staring along the non-zipper section work the same as previously. stopping the stitching 1/2" in from each corner and using a 1/2" seam allowance. clip corners and continue to the other side turning your work. Don't forget to open your zipper up before you finish.

Step 14: Clean Up the Mess

Zig zag stitch over the edges of the seams to minimize the fraying and increase the longevity of your project.

Step 15: Attaching the Webbing

Fold webbing in half and sew with 1" seam. mark with a pin the half way point.
Press open seam and place raw edges face down as shown. Arrange in a comfortable balanced position for your dish. the seam and the half way mark shout be parallel. I put them in the center. Once you are happy with the placement open the carrier and stitch the webbing down along each side only on the bottom of the carrier.