Lemonade is summer staple that doesn't need much improving, but if you want to take the classic beverage to a more refined and fancy place, try incorporating vanilla bean syrup. This secret ingredient rounds out lemon's natural harshness and tempers its acidity without detracting from the flavour we so firmly associate with summer.
The addition of the fragrant seeds will certainly boost sales at any neighbourhood lemonade stand, but it's worth trying even if you aren't in the footpath refreshment biz. You may not get paid in quarters, but you'll be paid many compliments.
Check the link below for exact instructions, but the key is to make a simple syrup of vanilla seeds, sugar, and water. (Two beans will give you enough syrup for three quarts of lemonade.) Once you've tried out the basic recipe, don't be afraid to play around with combinations. Strawberry-vanilla sounds like a real winner to me, and I'd love to see how those little specks play with a pitcher of Arnold Palmers.
Secret-Ingredient Lemonade [Food 52]