Combine raisins, splash of vinager and warm water into a bowl. Let sit for 20 minutes to allow raisins to plump up.
Cook pasta, reserving 1/2 cup of the cooking water.
Thinly slice chard stems and tear leaves into strips.
While pasta is cooking heat a few tblsp of olive oil in a large skillet over medium-low heat. Add sliced garlic and pine nuts and cook until lighly browned, about 5 minutes. Add chile flakes and cook for another few seconds before adding the drained raisins.
Increase the heat to medium before adding chard stems, salt and pepper. Allow the chard stems to soften before adding the chard leaves and a splash of pasta water.
Add the drained pasta and butter to the pan and combine well. Adjust the seasoning with more salt, pepper and chile flakes. Grate parmigiano over everything and drizzle with more olive oil.
Serve right out of the pan!
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