Brush the baguette slices with a little bit of olive oil and bake them for about 8 minutes. Take them out and set aside.
Lower the temperature to 375.
In a small pan, saute sliced onion on medium-high heat, until it starts to golden. Add the diced pears and saute for a couple more minutes. Mix in pine nuts and set aside.
Lay the crostini on a baking sheet, toasted side up and sprinkle with some salt.
Thinly slice the cheese and divide among the crostini, on the toasted side.