create table ingredients (
    id integer not null,
    name VARCHAR(255),
    primary key (id)
)
create table recipes (
    id integer not null,
    name VARCHAR(255),
    primary key (id)
)
create table cooked_ingredients (
    recipe_id integer not null,
    ingredient_id integer not null,
    quantity float
)
alter table cooked_ingredients
    add constraint fk_cooked_ingredients_recipe foreign key (recipe_id) references recipes
alter table cooked_ingredients
    add constraint fk_cooked_ingredients_ingredient foreign key (ingredient_id) references ingredients

Ingredient {
   private int id;
   private String name;
}

CookedIngredient extends Ingredient {
   private double quantity;
}

Recipe {
   private int id;
   String name;
   Collection<CookedIngredient> ingredients;
}