Mashed Potatoes with carrot

1 1/2 lbs russet potatoes , peeled, rinsed, cut into large chunks 3/4 lb carrot , trimmed, cut into 2-inch pieces 1 1/2 tablespoons unsalted butter , softened[...]

1 lb potato , peeled (we used a mixture of russets and Yukon Gold) 1 tablespoon fresh jalapeno, finely minced 1 small carrot , peeled and finely grated[...]