Here is an amazing list that can really help you out if you are new to cooking allergy free:
Substitution Chart- This information can be found on Living Allergy and Diabetes Free
Below is a list of some of my personal substitutions that I use on a regular basis for our own family. These may or may not work for you family depending on your allergens, please read the labels carefully:
Milk = Rice Milk
Butter = Earth Balance (Dairy Free Butter)
Shortening = Crisco
Buttermilk = 1 TBS of White Vinegar + 1 Cup Rice Milk (Let this sit 5 minutes)
Eggs = 1/4 cup applesauce per egg
Chocolate = Enjoy Life Chocolate Chips
Cream Cheese/Sour Cream = Tofutti
Sometimes baking allergy free can be a little trial and error, you’ll soon find out what substitutes you like best.