What specifically are the restrictions? There are many ways to make hoisin, knowing what you can and can not have may help.
You may be interested in browsing the Hoisin products from Soy Vay
Here is a recipe from Moon Dragon
:Homemade Hoisin Sauce Recipe
4 Tablespoons soy sauce (usual/dark/light)
2 Tablespoons peanut butter or black bean paste
1 Tablespoon honey or molasses or brown sugar
2 teaspoons white vinegar
1/8 teaspoon garlic powder
1/8 teaspoon onion powder (optional)
2 teaspoons sesame oil
20 drops chinese hot sauce, habenero or jalepeno
1/8 teaspoon black pepper
And another recipe posted here
Source: From my mother with love & more
Yield: About 2 bottles
1 cup vermouth, or sake (rice wine)
1 cup soy sauce
3/4 cup vinegar (not cider)
1-1/4 cup sugar
1 full tbsp. crushed garlic
1 tbsp. grated ginger
1 tsp. sesame oil
1 cup pitted plums
2 tbsp. wheat flour
1/4 tsp. each of anise, clove, and allspice
Cook for 10 minutes the pitted plums with the vermouth.
Mix the wheat flour with the vinegar and make a liquid batter.
In a stainless steel saucepan put all the ingredients, mix well until well blended and bring to a boil. Continue to mix until the sauce thickens. It should not be too thick, neither pudding like. With a hand blender, blend to a soft creamy sauce.
Transfer to warm bottles, or glass jars. Cool and seal air tight. Keep in the refrigerator.