I think it's because the orginal recipe called to put the biscuits on the bottom of the pan and then cover with the tuna mixture. Which was all fine and dandy, except that the biscuits didn't cook through then. They were still all doughy and gross because they didn't get the chance to bake up being all covered in goo. So as long as you put the biscuits on TOP of the tuna mixture, you should be golden!
...1 tube refrigerator biscuits
...1 c. milk
...1 can tuna
...1 can cream of mushroom soup
...1 can peas
...2 T. onion, chopped
In a large bowl, combine all ingredients except for the biscuits. Pour into a greased 9x9 pan. Place biscuits on top of the tuna mixture. Bake at 400 for 25-30 minutes, until the biscuits are baked through and browned.
To see more great recipes, check out Foodie Fridays over at Designs by Gollum and Food on Fridays over at Anne Kroeker!