Spray a 9-inch x 13-inch baking dish with non-stick cooking spray. Add the chopped honey buns to a dish and set aside.
In a large mixing bowl, whisk together the eggs, sugar, melted butter, cinnamon, and vanilla until combined. Add the milk and whisk until just combined.
Pour the custard mixture over the honey buns. Use a spoon to press down on the honey buns so they are submerged. Let everything sit for 30 minutes so the buns can soak up the custard.
Preheat your oven to 350 degrees F. Bake for 45-50 minutes or until the top is browned and puffed. A knife inserted in the center should come out clean.
Remove the bread pudding from the oven and let cool for at least 30 minutes before serving. (It's great warm, at room temp, or cold.)