Using a serrated bread knife in a gentle sawing motion, trim and discard crusts from bread slices to make each slice a 3-inch square. Cut each square diagonally into 4 triangles.
Using a bread triangle as a guide, cut 12 triangles each from turkey, cheese, and pear slices.
Spread a layer of aïoli onto each bread triangle. On 6 bread triangles, layer a turkey triangle, a cheese triangle, and a pear triangle. Cover each with a remaining bread triangle, aïoli side down.
Serve immediately, or cover with damp paper towels, place in a covered container, and refrigerate for a few hours until serving time.
Just before serving, garnish each sandwich with fresh sage leaves, if desired.
Recipe by TeaTime Magazine at https://teatimemagazine.com/turkey-pear-tea-sandwiches/