3 pears, divided
1 1/2 cups flour
1 1/2 teaspoons baking powder
1/4 teaspoon baking soda
1/2 teaspoon salt
2 teaspoons fresh lemon zest
3/4 cup plus 3 tablespoons sugar, divided
3 large eggs
1 cup mascarpone, room temperature
2 tablespoons olive oil
Heat oven to 350 degrees F. Lightly grease and flour a 10-inch spring form pan. Peel the pears; chop one into small pieces for the batter, and slice the other two in lengthwise slices and reserve.
In a medium bowl, combine the flour, baking powder, baking soda and salt and stir to mix, then add lemon zest. Reserve. In a large bowl with an electric mixer, combine the sugar and eggs and beat for 2 minutes. When the eggs are light yellow and frothy, add the mascarpone and olive oil and beat until smooth. Use a spatula to fold the flour mixture into the egg mixture, being careful not to over-stir. Fold in the chopped pears.
Spread the batter in the spring form pan and smooth the top. Arrange the pear slices in a pinwheel design on top of the cake, and sprinkle with the remaining 3 tablespoons sugar. Bake for 55-60 minutes, until a toothpick inserted in the center of the cake comes out with only moist crumbs attached. Cool on a rack, then run a paring knife around the edges of the cake and remove the spring form rim. Serve immediately, or store, tightly wrapped, for up to 3 days at room temperature.
Serving Suggestion: This moist fruit-forward cake really requires no frosting, but you could add a decorative sprinkling of powdered sugar to the top before you serve with dark, rich demitasse cups of espresso.