This simple trick to straighten and crisp bacon does mean another pot to wash, but that's a fair price to pay for bacon that's perfectly flat and crisp all over.
Place the bacon in a large sauté pan, being careful not to crowd the pan. Place a pot that's slightly narrower than the bottom of the sauté pan on top of the bacon to weight it down and keep it flat. Cook the weighted bacon over medium heat so the fat renders slowly and completely. After the bacon is browned on one side, about 2 to 3 minutes, carefully lift the pot (it'll drip), flip the bacon, and replace the pot. Cook the bacon on the other side until it's completely browned and crisp, 2 to 3 more minutes.