Adapted from Cook's Country
1/2 cup panko bread crumbs, ground in food processor
1 tablespoon butter, at room temperature
2 pounds russet potatoes, peeled
1 1/4 cups half and half
1 1/4 teaspoon salt
1/2 teaspoon freshly ground black pepper
1 1/3 cups shredded sharp cheddar
2/3 cup grated Parmesan
2 teaspoons cornstarch
Preheat oven to 425º. Butter 12 cup muffin tin, then dust each cup with panko crumbs. Set aside.
Cut potatoes in half lengthwise, then each half into 3 spears. Slice the spears into 1/4 inch slices. Place in large microwave safe bowl and add half and half, salt and pepper. Mix to combine. Cover with plastic wrap and microwave 12-15 minutes, stirring once, till tender.
Toss cheddar, Parmesan and cornstarch in bowl. Add all except 1/3 cup to hot potatoes, and stir till well mixed. Divide mixture between muffin cups and smooth tops. Sprinkle with reserved cheese.
Bake, covered, for 10 minutes, then remove cover and continue baking 13-15 minutes, till lightly browned. Remove to cooling rack and run knife around perimeter of each cup. Cool 5 minutes then invert onto baking sheet, tapping if necessary to release. Cool 5 minutes and serve.