This is such a wonderful way to preserve the flavors of spring. I love adding this syrup to my morning matcha latte, but I think it would be wonderful in all manner of hot tea and coffee beverages, as well as a flavor booster for whipped cream, pancakes, and lots of other goodies.
A couple things to note, though: only use lilacs from a source that you know isn't using pesticides on their flowers. If you get them from a florist, there's a solid chance they've been sprayed, so make sure to check with the florist before you prepare them for consumption. If they're in your garden, you're good (presuming you're not using pesticides. If so, please stop! It's terrible for honey bees + the environment.) Also, don't over-steep the flowers. They can begin to decompose quickly because of the heat and the sugar, so as long as you stick to the directions below you'll be fine. Enjoy, my friend!
Bring the sugar and water to a boil in a medium saucepan over medium heat, stirring every few minutes.
Allow the syrup to boil for 5 minutes, then remove from heat and cool for 10 minutes.
Place the lilac blossoms in a large heat-proof pot. Pour the syrup over the blossoms, then stir to make sure they're covered in syrup. Place the lid on the pot and let the mixture infuse for 2 to 3 hours. I'd be cautious about letting them infuse for too much longer, as the sugar in the syrup combined with the heat can speed-start the decomposition process of the flowers, and the delicate aroma and flavor of the lilacs can turn into the smell and taste of an old vase of flowers, unfortunately.
Pace a fine mesh sieve over a large bowl and pour the syrup and lilac mixture into it, straining out the blossoms. Compost the blossoms in your yard or bin. Pour the syrup into clean glass containers and seal tightly.
Refrigerate the syrup, and use to add a little flavor of spring to your sweets + beverages. I especially love this with my morning matcha latte! The syrup will keep in the refrigerator for up to 2 months.