Gently crush cardamom with a rolling pin or the bottom of a skillet to slightly crack open pods without releasing seeds. Combine cardamom, wine, sugar, lemon juice, saffron, and salt in a medium saucepan over medium heat, stirring until sugar dissolves. Bring to a simmer. Add pears; add water if needed to completely submerge pears. Cover with lid slightly ajar and simmer, turning occasionally, until pears are tender but not mushy, about 30 minutes.

Using a slotted spoon, transfer pears to a plate. Increase heat and boil poaching liquid until reduced to 1 cup, 10-15 minutes.

Do ahead: can be made 8 hours ahead. Cover and refrigerate pears. Let syrup stand at room temperature. Rewarm syrup before continuing.

Spoon some syrup over cold or room temperature pears. Serve with a dollop of crème fraîche; pass remaining syrup.