In a saucepan, mix the sugar and vinegar at a low temperature until the sugar has dissolved. Low temp is better for the sugar.
Clean the berries and place them into the 16 oz washed jar.
Add the lavender flowers to the jar as well.
Let the vinegar and sugar mixture come to room temperature and pour over the fruit.
You can use a fork or muddle to break the berries apart a bit or let them stay whole.
Seal the jar with a clean lid and let sit in the fridge for several day to a week. Depends on you technique as to how long it will last. Usually at least up to a month.
If you think of it, you can turn the bottle several times per day while the flavors are mingling.
You can strain the fruit as you pour it or add the fruit into drinks. If you strain the fruit, it can be used in other dishes or baking.
Some recipes call for mixing the berries and sugar and then several days later adding the vinegar. I prefer this method for ease and completion in the recipe in one day.