In a large bowl, mash up avocado with a fork so it becomes chunky. Then add in yogurt, Dijon and garlic. Mix it together and add more garlic or Dijon to taste.
Fold in the remaining ingredients, being careful not to over mix – the salad should be chunky, with a lot of texture. Season to taste with sea salt & pepper, and if desired, freshly squeezed lemon juice.