1) Cut the tops of the tomatoes and set aside. 2) Scoop out the seeds from the tomatoes and discard. 3) Season the tomato cases. 4) Mix the tuna, mayonnaise, olives, tabasco and lemon juice together. 5) Divide tuna mixture between the tomato cases, filling each one generously. 6) Place the lids on the tomatoes, pressing down to gently secure. 7) Garnish with parsley and serve.