Prepare a boiling water bath canner and four half pint jars. Place lids in a small saucepan and bring to a bare simmer.
Peel peaches and dice. Combine them with the honey in a medium bowl. Split open a vanilla bean and scrape out all the vanilla seeds with the blade of a paring knife. Add both the seeds and the split bean to the peaches and honey. Stir to combine.
Let the peaches and honey sit for at least 10 to 15 minutes, so that the honey can help make the peaches juicy.
When you're ready to cook, scrape the peaches, honey, and vanilla into a 4 quart Dutch oven. Place over high heat and cook, stirring regularly, until the peaches have broken down and it looks quite thick and jammy.
Taste the jam and determine whether you think it could use the flavor balancing of the lemon zest (it will mellow it out if you feel it's too sweet). If you prefer it without the lemon zest, feel free to skip it.
Remove the pan from the heat. Fish out the vanilla bean and set aside. Funnel jam into prepared jars. Wipe rims, apply lids and rings, and process in a boiling water bath canner for 10 minutes (don't start your timer until the pot returns to a boil).
When the time is up, remove jars from the canner and place them on a folded kitchen towel to cool.
When the jars are cool enough to handle (let them rest at last an hour or two), remove rings and test seals. Unsealed jars should be refrigerated and used promptly. Sealed jars are shelf stable for up to a year.