Reconstitute the gelatin sheets in water.
Warm the milk for about 1.5 minutes in the microwave at 500 W and dissolve the gelatin.
Remove the stone from the avocado, and combine with sugar, lemon juice, and salt in a food processor. Thin the mixture out with the milk.
Tilt the glasses, and pour Step 3 into them. Chill for at least 1 hour in the fridge to harden (make sure they're firming up properly).
Wash your bell pepper, place in a lidded container and microwave for 10 minutes at 500 W or roast it in an oven.
Soak the bell peppers in water and peel off the skin. Remove seeds and stem. It might be a bit harder to peel if you used a microwave.
Warm milk and dissolve the gelatin in it.
Place the Step 6 bell peppers, sugar and salt in the food processor, and blend with the milk.
Once you are sure the avocado has firmed up, pour the bell pepper mixture from Step 8 into the Step 4 glasses. Chill in refrigerator.
Blanche the tomato to remove the skin, remove seeds, and cut into 5 mm cubes.
Toss Step 10 with lemon juice, sugar, salt, tabasco and let sit for a while.
Top Step 9 with 11 and serve.