Blueberries: I always like to use fresh ingredients when I can and when I'm not feeling too tired that day. But frozen berries work just fine and come out tasting like no one changed a thing. If using frozen, thaw them out, dry and then toss them moderately in flour. This will help them not to sink too far into the bottom of the pan!

• Replace the blueberries with any other fruit, I'd love to see how it turns out!

Lemons: Once again, fresh lemons are always the way to go! However, I've been thinking of a theory that bottled lemon juice might come out with a more consistent taste. Not only that, more times than not, I've had half my batch sucked dry before they even got to me.

Butter: I prefer to use unsalted butter because butter/margarine can vary in the quantity of salt. Using salted butter is fine, just make sure that you leave out the extra rock salt. This will help ensure you cake is not more salty than it is sweet. Yuck!

Milk: If you're sensitive to dairy or lactose intolerant, feel free to use soy milk or almond milk. In a real pinch or if you don't feel like waiting for the next grocery run (like me) you can also substitute milk for half-and-half at a one-to-one replacement. For example, if the recipe calls for 1/2 C of milk, replace with 1/2 C of half-and-half.

Sour Cream: Can be substituted with plan Greek yogurt. Flavored yogurt can be used but...used at your own risk.

Egg Whites:  The whole egg can be used for this recipe and will not alter the end results in many ways other than color, just half the amount of sour cream used. I personally prefer the effect that egg whites create with the contrast of colors, white, and blue, or purple lol.