In a bowl mix together the tomatoes, onion, garlic, fennel seed, basil, 1/3 cup olive oil, salt and pepper. Chill for at least 1 hour to blend the flavours.
Preheat oven to 180 degrees C.
Brush both sides of bread slices with some of the 1/4 cup of olive oil; place slices onto a baking tray. Toast the bread until golden brown and crunchy on the outside, about 3 minutes per side. To serve, spoon the tomato mixture onto the toasted bruschetta and arrange on a serving platter.