Six Recipe Substitutions For Common Ingredients

So you know how you found that awesome recipe on Pinterest the other day? You've been dying to make it and have finally found the time. So you pull out the ingredients only to realize that it calls for buttermilk. Buttermilk? Who keeps buttermilk in their fridge on a regular basis? And why?? Now what? You can save it for another day when you finally remember to add that missing ingredient to your grocery list OR you can substitute. Oh yes.

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Here are 6 substitutions for commonly used (and forgotten) ingredients:

If you don't have lemon juice
1 teaspoon of lemon juice = 1/2 teaspoon of white wine vinegar

If you don't have cake flour
1 cup of cake flour = 1 cup less 2 tablespoons of all-purpose flour

If you don't have buttermilk (because seriously, who does?)
1 cup of buttermilk = 1 cup of milk plus 1 tablespoon lemon juice or 1 cup of plain yogurt

If you don't have brown sugar
1 cup of brown sugar = 3/4 cup of granulated sugar plus 1/4 cup of molasses

If you don't have heavy cream
1 cup of heavy cream = 2/3 cup of milk plus 1/3 cup of melted butter

If you don't have ricotta cheese
1 cup of ricotta cheese = 1 cup of cottage cheese


And just for the record, I refuse to buy buttermilk. Because it never gets used unless it's for a recipe. And then I end up with a bunch leftover buttermilk to spoil in the fridge. So much easier to substitute.

What do you guys do? What ingredients have you found to substitute when you're in a pinch?