It's not fair to call such a beautiful tart a "scrap" tart, but that's the name that applies. First conceived by writer and food stylist Erin Jeanne McDowell, this tart originally used up leftovers from several open bags of nuts. The phyllo crust is oh-so-crisp, and is a simpler option that's perfect when you're not up for a full-on pie crust.
Preheat the oven to 375°F, preferably with a baking stone on the bottom rack. Lightly grease a 10" tart pan and place it on a foil-lined baking sheet.
To make the crust: In a small bowl, combine the sugar and cinnamon. Place one sheet of phyllo on your work surface and brush it all over with some of the butter. Sprinkle with a heaping teaspoon of the cinnamon sugar.
Place the next piece of phyllo on top, slightly askew, so that the corners of the two sheets don't match up. Brush with butter and sprinkle with cinnamon sugar. Repeat with the remaining sheets of dough, butter, and cinnamon sugar. The finished crust should look like a sunflower, with multiple points from the phyllo corners poking out all around.
Carefully transfer the assembled crust to the prepared tart pan. Press the crust carefully into the base and the corners, to make sure it sits evenly in the bottom of the pan.
To make the filling: Sprinkle the nuts into the lined pan, spreading them evenly with your fingers to be level with the rim of the pan.
Whisk the melted butter, brown sugar, honey, salt, and vanilla together in a medium bowl. Add the eggs one at a time, whisking until the custard is smooth. Slowly pour the custard over the nuts.
Bake the tart on the baking stone, or bottom rack of your oven, until the custard is set at the edges but still wobbles in the center, 33 to 36 minutes. The nuts should look lightly golden, and the crust should be evenly browned. Remove from the oven and cool completely before slicing.
Refrigerate any leftover tart for a day or so; freeze for longer storage.
