Individual Zucchini Souffles

flute zucchini with a zester or peeler, cutoff ends cut each zucchini into 3/4-inch thick slices using a melon baller, scoop out the top half of each slice steam zucchini until almost tender, drain, and cool line a baking sheet with parchment paper place zucchini cups upright onto baking sheet heat butter in a small skillet, over a medium flame whisk in flour to make a blonde roux gradually whisk in milk, heat and stir until thickened remove from heat and allow to cool slightly whisk in egg yolk, cheddar, mustard, salt, and pepper fold stiff whites into yolk mixture spoon into zucchini cups, filling to the top place baking sheet onto top rack of oven bake @ 425 degrees for 5-8 minutes, until puffed and golden serve hot