I followed the recipe exactly. It said to bake at 350 and I did.
Ideas on cause of problem:
1) To bake at specified heat, get an oven thermometer & make sure the inside temperature is what your recipe needs.
2) Even if the oven temp is correct, outer part of the cake is baking too quickly and by the time it is tough/dry the inside is still wet. So, lower the oven temp 25 degrees F and bake longer, testing as needed for doneness.
3) To distribute heat better, consider using a pan with a hole in the middle (angel-food or Bundt styles), or get a baking cone you can insert in the middle of a regular pan to allow hot air into the middle.
4) Haven't seen the recipe so can's say anything about it. Perhaps use another tried and true recipe. Make the pumpkin version of this AtoZ Cake - tasty & reliable (recipe adapted from Nancy Clark, Sports Nutrition)
Needed to be baked longer. Yesterday I made 2 zucchini breads.
One was done at the exact recipe time, the other was not done in the middle. Ten more minutes and the toothpick came out clean. The sides didn't burn.
Your elevation is a factor. Where do you live/bake?
You overmixed it and did not cook it long enough
Thank you to all who replied! Took each of your advice and it came out a lot better :)