This gingerbread packs a peppery triple-punch thanks to three forms of ginger—ground, fresh and candied. Butternut squash keeps the crumb plush and moist. For ease, we use frozen squash, sold in 10- or 12-ounce packages. Either size works, but the 12-ounce size makes for a slightly denser cake. To use fresh butternut, substitute 10 ounces of peeled and cubed squash; it will cook in the same amount of time. Pay attention to the baking cues; underbaking will give the cake a heavy, spongy crumb, so it’s better to err on the side of overdone.