Lightly brush the baguette slices with olive oil and grill until lightly toasted. (I use a grill pan.)
Place the rest of the ingredients in a bowl. Mix well and allow to sit for 10 minutes at room temperature to allow the flavors to meld.
Top the toasted bread with the tomato mixture and serve.
*Chiffonade is a fancy French term for slicing herbs or other leafy greens into thin strips. This is accomplished by stacking the leaves, rolling them tightly like a cigar, and finely slicing them perpendicular to the roll.