Cut and seed the capsicums and cut into large slices. Place these under a hot grill and cook until the skins are blackened and blistered. Place the black peppers into a double thickness plastic bag and seal, allowing them to steam. Set aside for thirty minutes. Remove the peppers from the bag and remove the pepper skins. Slice the leek lengthways and separate the leaves. Wash in cold water to remove all the grit, then plunge the cleaned leaves into a pot of boiling water. Boil for-2 minutes, then remove the leek and rinse under cold water. Dry well. Line a standard loaf tin with plastic wrap then drape the leek leaves over the base and sides of the tin, allowing the long ends to hang over the sides. Heat the butter and saute the spring onions until softened. Mix the softened cream cheese, goats cheese, herbs and spring onion mixture in the large bowl of an electric mixture. Sprinkle the gelatine over the cold water and allow to soak for 1 minute. Place the gelatine mixture in the microwave and heat for 20 seconds on medium until the mixture is boiling (watch carefully to avoid boil-over) Stir well with a fork. Add the dissolved gelatine and cream to the cheese mixture and mix to combine thoroughly. Pour one third of the cheese mixture into the prepared loaf pan and cover with alternate red and yellow pepper slices. Cover with another third of the cheese mixture, repeating the capsicum layer. Finish with remainder of cheese mixture, then drape the leek overhang back over the cheese filling to enclose. (Use any left over leek to fill in the gaps if necessary.) Chill overnight. To serve, remove the terrine from the loaf tin and discard the glad wrap. Using an electric knife slice thick, even portions of the terrine. Place a slice of the terrine on each plate and sprinkle with the tomato, cucumber and olives. Whisk the vinegar, oil and mustard together and drizzle over. Per serving: 1429 Calories (kcal); 144g Total Fat; (88% calories from fat); 16g Protein; 26g Carbohydrate; 274mg Cholesterol; 1490mg Sodium Food Exchanges: 0 Grain(Starch); 1 1/2 Lean Meat; 3 1/2 Vegetable; 0 Fruit; 28 Fat; 0 Other Carbohydrates Converted by MM_Buster v2.0n.