Roast the hazelnuts for 10 minutes at 210°C. Set aside about twenty hazelnuts for decoration.
Roughly chop the pears and place them in a saucepan with the pear condiment and water. Cook covered over medium heat until the pear is fully cooked. Add the agar-agar and cook for two additional minutes. Blend with an immersion blender and refrigerate.
Add the flour, defatted hazelnut powder, softened butter, brown sugar, caster sugar, baking powder, egg, and pinch of fleur de sel. Mix by hand until you obtain a homogeneous dough. Lightly crush the roasted hazelnuts and add them to the mixture.
Form small dough balls of 15–20 g each. Place them in a mold or on a baking tray lined with parchment paper.
Preheat the oven to 190°C and bake for 5 minutes. Allow to cool before unmolding (if using a mold). Top with a bit of pear gel and half a hazelnut.