Russet Potato Gratin

INGREDIENTS
4 large or 5-6 medium russet potatoes, peeled and sliced to about 1/8" thick
2 medium yellow onions, sliced medium
6oz grated Gouda
2oz grated Romano
2 C half & half
3 T chopped fresh parsley
3 T chopped fresh chives
1 1/2 tsp salt
1 tsp fresh ground pepper
3 T butter

DIRECTIONS
Preheat oven to 375F. Lightly oil a 9"x13" baking dish (you can use any shallow pan here--we used a larger one so the gratin would be thinner and crustier).

In a skillet over medium heat, heat 1 tablespoon of butter and 1 tablespoon of olive oil. Add onions and cook, without browning, until soft, about 7 minutes. Take pan off heat and allow to cool somewhat (the onions can be warm but shouldn't be hot to the touch).

While onions are cooking, whisk half & half, herbs, salt and pepper in a bowl until combined. Set aside.

Add sliced potatoes in a single layer, slightly overlapping.

Add half onions, scattering over potatoes. Add half of the grated cheese mixture.

Repeat with potatoes, onions and cheese mixture. Add herbed half & half mixture last, drizzling over the potatoes to evenly distribute the herbs.

Use your hands to press down onto the potatoes. The milk mixture should not cover the potatoes completely, but it should be a close call.

Cover with foil and bake for 1 hour. Remove foil and bake for another 20-30 minutes until very golden and bubbly. Allow to sit for ten minutes before serving.

{from Eating Seattle}