How to set dynamic many to many in factory boy with through table?

I've just recreated this setup and I'm struggling to see what the problem is. Here are several tests that demonstrate that all seems to be working well? Or am I misunderstanding the question?

# create recipe ingredient and recipe ingredientrecipe = RecipeFactory(name="recipe1")ingredient = IngredientFactory(name="ingredient1")recipe_ingredient = RecipeIngredientFactory(recipe=recipe, ingredient=ingredient)# recipe created?       r = Recipe.objects.all().first()self.assertEqual(r, recipe)# ingredient created?i = Ingredient.objects.all().first()self.assertEqual(i, ingredient)# recipe ingredient created?ri = RecipeIngredient.objects.all().first()self.assertEqual(ri, recipe_ingredient)        # test many to manyself.assertEqual(ri, r.recipeingredient_set.all()[0])self.assertEqual(ri, i.recipeingredient_set.all()[0])# add a new ingredient to recipe 1ingredient2 = IngredientFactory(name='ingredient2')recipe_ingredient2 = RecipeIngredientFactory(recipe=recipe, ingredient=ingredient2)# test many to manyself.assertTrue(recipe_ingredient in r.recipeingredient_set.all())self.assertTrue(recipe_ingredient2 in r.recipeingredient_set.all())# create a pre-existing recipe and a set of ingredientspizza_recipe = RecipeFactory(name='Pizza')cheese_on_toast_recipe = RecipeFactory(name='Cheese on toast')cheese_ingredient = IngredientFactory(name='Cheese')tomato_ingredient = IngredientFactory(name='Tomato')pizza_base_ingredient = IngredientFactory(name='Pizza base')toast_ingredient = IngredientFactory(name='Toast')# now put togetherRecipeIngredientFactory(recipe=pizza_recipe, ingredient=cheese_ingredient)RecipeIngredientFactory(recipe=pizza_recipe, ingredient=tomato_ingredient)RecipeIngredientFactory(recipe=pizza_recipe, ingredient=pizza_base_ingredient)RecipeIngredientFactory(recipe=cheese_on_toast_recipe, ingredient=cheese_ingredient)        RecipeIngredientFactory(recipe=cheese_on_toast_recipe, ingredient=toast_ingredient)        # test pizza recipepizza_ingredients = [cheese_ingredient, tomato_ingredient, pizza_base_ingredient]pr = Recipe.objects.get(name='Pizza')for recipe_ingredient in pr.recipeingredient_set.all():    self.assertTrue(recipe_ingredient.ingredient in pizza_ingredients)# test cheese on toast recipecheese_on_toast_ingredients = [cheese_ingredient, toast_ingredient]cotr = Recipe.objects.get(name='Cheese on toast')for recipe_ingredient in cotr.recipeingredient_set.all():    self.assertTrue(recipe_ingredient.ingredient in cheese_on_toast_ingredients)# test from ingredients sidecheese_recipes = [pizza_recipe, cheese_on_toast_recipe]ci = Ingredient.objects.get(name='Cheese')for recipe_ingredient in ci.recipeingredient_set.all():    self.assertTrue(recipe_ingredient.recipe in cheese_recipes)