Tartines with Gruyère and Greens
Adapted from Grow, Cook, Eat
Makes 6 large tartines

If you make them this way, they are kind of meal size.  Terrific with a bowl of pea soup or a hearty salad.  If you want more appetizer servings, use smaller slices of bread.  The topping can be made a day in advance and refrigerated, but definitely serve these just out of the oven.

2 cups grated Gruyere cheese (about 8 ounces)
3 tbsp. very soft unsalted butter
1 tsp. Dijon mustard
¼ cup finely chopped radishes
2 tbsp. fresh chives, chopped
Pinch of salt and few grinds of pepper
6 ½-inch thick slices good bread, such as pain de campagne
Olive oil
1 small bunch soft greens, such as mustard greens or spinach

Preheat the oven to 375F.  In a medium bowl, use a fork to really mash the butter.  Add in the cheese and mix well to combine the two.  Add the mustard, radishes, chives, and salt and pepper.  Divide the mixture between the bread slices, pressing down slightly.  Place the bread on a baking sheet and toast until the cheese puffs up and is lightly browned, 12 to 15 minutes.

Meanwhile, place a skillet over medium heat.  Drizzle in just enough olive oil to coat the bottom of the pan, then add the greens.  Cook, stirring frequently, until wilted, 5 to 10 minutes, depending on the green.  Spread the wilted greens on evenly over the cheesy toasts and serve immediately.