Heat oven to 400°. Coat the interior of a 1 1/2-quart gratin or baking dish with the softened butter and spoon in the 2 tablespoons of bread crumbs; tilt the dish around until they cover the buttered surface.
Wash chard in cold water. Drain briefly, then cut off the chard stems and separate them from leaves. Slice stems and leaves into 1 1/2-inch pieces.
Heat the olive oil in a 6-quart Dutch oven or soup pot over medium heat; add the shallot, garlic, and stems of the chard; cook, stirring constantly, until softened but not browned, about 3-5 minutes. Add the chard, sprinkle with salt, cover tightly and steam until the chard has wilted to half its original volume, about 5 minutes.
Uncover and cook the chard, turning occasionally with tongs, until all the water in the pan evaporates, about 5 more minutes. Season with pepper and set aside.
Melt the butter in a small saucepan over medium heat; whisk in the flour; cook, whisking, until mixture bubbles up and turns lighter in color, about 1 minute; pour in the cold milk all at once; whisk vigorously; add salt and bay leaf; heat, whisking, until it comes to a boil and thickens, about 5 minutes; reduce the heat to low, simmer 2 minutes; stir in the nutmeg, oregano, and thyme; remove from heat and discard bay leaf.
Mix the cooked chard and the sauce; spoon into prepared pan; sprinkle with remaining 1/4 cup bread crumbs and the cheese; bake until golden and bubbly, 35 minutes.
adapted from RecipeZaar, originally from the Chicago Tribune