How to Make It
Preheat oven to 350°F. Grease a 12-cup muffin tin with softened butter, and dust with flour; set aside. Stir together dates and 1 cup water in a small saucepan. Bring to a boil over medium; cook, stirring occasionally, until dates are softened and liquid is mostly absorbed, about 5 minutes. Remove from heat, and let cool 5 minutes. Using a potato masher or fork, mash mixture until mostly smooth; set aside.
Stir together flour, cinnamon, baking powder, baking soda, and salt in a bowl; set aside. Place brown sugar and butter in bowl of a stand mixer fitted with the paddle attachment; beat on medium-high speed until light and fluffy, 4 to 5 minutes. Add eggs, 1 at a time, beating well after each addition. With mixer running on low speed, gradually add flour mixture, beating until just combined, 1 to 2 minutes, stopping to scrape down sides of bowl as needed. Stir in date mixture. Fold in pear pieces.
Spoon batter evenly into prepared muffin tin, filling each cup about 1/3 inch from top (about 1/3 cup each). (Discard any remaining batter, or reserve for another use.) Bake in preheated oven until a wooden pick inserted in centers of cakes comes out clean, 18 to 22 minutes.
Melt butter in a medium saucepan over medium-low. Add brown sugar and miso; whisk until dissolved, 1 to 2 minutes. Whisk in heavy cream. Let mixture come to a boil; cook, whisking constantly, 1 minute. Remove from heat; set aside until ready to use.
Once cakes are finished baking, remove from oven; immediately poke holes all over cakes with a wooden pick. Spoon about 1 tablespoon miso-caramel sauce over each cake. Let cakes cool in muffin tin 20 minutes, occasionally poking additional holes to help sauce soak in.
Beat heavy cream in bowl of a stand mixer fitted with the whisk attachment on medium-high speed until soft peaks form, 1 to 2 minutes.
Run a small offset spatula around each cake to help loosen from muffin tin. Invert cakes onto individual serving plates; top each with about 1 1/2 tablespoons miso-caramel sauce. Serve with whipped cream and remaining miso-caramel sauce.