Add the onions and tarragon vinegar in a bowl and let stand for 5 minutes. Add the pear, green onions and tomato and lightly toss

Slice the French bread long ways and spray or brush with olive oil. Toast under the boiler, or they can be grilled until golden brown

Assemble the bread: add the prosciutto on top of the bread, then add some of the pear topping and finish off with the feta crumble