You’re halfway through a recipe. The oven is preheating; your ingredients are lined up, and then you realize something is missing – quick, what’s a good buttermilk replacement?

When you suddenly remember that grandma’s chocolate chip cookie recipe wasn’t created with your plant-based era in mind, don’t give up! A few reliable substitutions for common baking ingredients like eggs, buttermilk and baking powder can keep everything on track. 

These practical fixes are just a few of those featured in The Food Substitutions Bible, Third Edition, a comprehensive reference with more than 8,000 tested substitutions for real kitchens. 

Buttermilk provides acidity, which helps baked goods rise and develop a tender texture. When it’s missing, you need to recreate that same balance. 

Substitute 1 cup (250 mL) buttermilk with: 

• 1 cup (250 mL) milk + 1 tbsp (15 mL) lemon juice or vinegar (let stand until slightly thickened) 

• ¾ cup (175 mL) yogurt or sour cream + ¼ cup (60 mL) milk 

These options work because they restore the acidity that interacts with baking soda or baking powder, helping maintain structure and texture. 

Did you know this method works with milk alternatives, too? Almond, soy or oat milk can be combined with lemon juice or vinegar in the same way, making this a flexible buttermilk replacement for dairy-free baking.

Baking powder is a complete leavening agent, meaning it contains both an acid and a base. If you run out, you can recreate that balance. 

Substitute 1 tsp (5 mL) baking powder with: 

• ¼ tsp (1 mL) baking soda + ½ tsp (2 mL) cream of tartar 

If cream of tartar is not available, baking soda can still be used, but it must be paired with an acidic ingredient already present in the recipe, such as yogurt, lemon juice or molasses.

Eggs contribute structure, moisture and binding. The best substitute depends on what role the egg is playing in your recipe. 

Substitute 1 egg with: 

• 1 tbsp (15 mL) ground flaxseed + 3 tbsp (45 mL) water (let stand until gelled) 

• ¼ cup (60 mL) unsweetened applesauce 

A flax mixture works best in denser baked goods like muffins or cookies, while applesauce is ideal when moisture is the priority. 

Successful substitutions come down to understanding function and a bit of chemistry. Ingredients are not just about flavour; they control how a recipe behaves. Acidity affects rise, eggs provide structure and leavening agents create lift. 

Once you understand those roles, substitutions become far less risky. Even if the result is slightly different than the original recipe, it can still be successful and, in most cases, just as good. 

If you want a complete, go-to reference for these situations, The Food Substitutions Bible, Third Edition belongs in your kitchen. It gives you the exact measurements, options and flexibility you need to keep baking, no matter what is missing. Pick up your copy to explore thousands of ingredient swaps and keep every recipe within reach.