Preheat the oven to 350F (180C).
Butter a 9″ (23cm) diameter round mold and sprinkle with sugar. Set aside.
Peel and core the pears.
Cut 2 pears into slices, cut the other two into cubes and set aside.
Lightly brown the pear slices in a pan with butter and 2 tablespoons of sugar.
Arrange them at the bottom of the reserved mold.

Using an electric mixer, whisk the eggs with the sugar until the mixture is light and fluffy.
While whisking, add the oil and Frangelico, then incorporate the flour that has been sifted beforehand with the salt, baking powder, and cinnamon.
Mix well.
Add the cubed pears and mix with a spatula.

Pour the batter over the pears, bake for 45 to 50 minutes or until a toothpick inserted into the center comes out clean.
Unmold by flipping the mold onto a serving plate.