Step 1 Place the raisins in a small bowl and cover with warm water to soften.
Step 2 Clean the chard: Separate the stems from the leaves and cut the stems into 1-inch segments. Shred the leaves, then wash them well and keep them in a bowl with the water that clings to them.
Step 3Cut the onion in half and then into thin half-moon slices. Heat 3 tablespoons olive oil in a large skillet and add the onions. Cook until they soften, 3 to 4 minutes. Add the garlic and cook until fragrant, an additional minute or two.
Step 4Add the cut-up stems, 1 teaspoon lemon zest, red pepper and 1 teaspoon salt. Cover and cook over medium-low heat until the stems are quite tender, about 20 minutes, stirring occasionally.
Step 5While the stems are cooking, toast the bread crumbs. Combine them in a small saucepan with the remaining one-half teaspoon lemon zest and 1 to 2 tablespoons olive oil. Stir to coat well; there should be only a light trace of oil in the bottom of the pan. Season with a pinch of salt and place over medium-high heat. Cook, stirring constantly, until the crumbs have darkened and toasted, about 5 minutes. Transfer them to a small bowl and set them aside to cool slightly.
Step 6When the stems are quite tender, add the shredded leaves, with the water that clings to them, and the golden raisins. Season with another teaspoon of salt and cook, stirring frequently, until the leaves are wilted and very tender, about 5 minutes. Season generously with black pepper and stir in lemon juice. Taste and add more salt if necessary. There should be only a little moisture left in the bottom of the pan; if there is more, drain it.
Step 7If you're going to serve the chard as a main course, divide it among 4 shallow pasta bowls and sprinkle each with about 2 teaspoons of toasted bread crumbs. If serving as a side dish, transfer the chard to a platter or a shallow serving bowl and sprinkle about one-half cup of bread crumbs over top. Pass additional bread crumbs at the table.