Creamed Swiss Chard with Lemony Breadcrumbs

Preheat oven to 400 °F. Toss breadcrumbs, oil, and lemon zest on a rimmed baking sheet; season with salt. Toast, tossing once, until golden brown, 8 –10 minutes. Meanwhile, cook chard leaves in a large pot of boiling salted water until tender, about 1 minute. Drain; transfer to a bowl of ice water to cool. Drain and squeeze well in a clean kitchen towel to remove excess moisture. Heat butter in a large saucepan over medium heat. Add shallots and chard ribs and stems, season with salt and pepper, and cook, stirring often, until tender, 5 –8 minutes. Add cream; bring to a boil, reduce heat, and simmer, stirring often, until thickened, about 4 minutes. Add chard leaves and cook, stirring, until warmed through and coated with cream sauce; season with salt and pepper. Top Swiss chard with breadcrumbs just before serving.