Slice the chard stems from the leaves. Coarsely chop the stems and set aside; cut the leaves crosswise into 1-inch-wide strips and set aside.
Heat the oil in a medium frying pan over medium heat until shimmering, about 3 minutes. Add the onion, anchovies, and raisins and cook, stirring occasionally, until the onion has softened, about 4 minutes.
Add the capers and garlic and cook, stirring often, until the garlic is fragrant and lightly browned, about 1 minute. Add the reserved chard stems and cook until they start to brown, about 2 minutes.
Add the chard leaves and cook, stirring the leaves with tongs, until they're wilted, about 5 minutes. Stir in the olives, pine nuts, and lemon juice, season with salt and pepper, and serve immediately.
This recipe can be made with beet, mustard, turnip, or older dandelion greens in place of the chard; serve it with grilled meat or fish, or eat the greens on their own with a dollop of tangy yogurt.