Mix the merlitons, onions, bell peppers, carrots and cauliflower in large bowl. Cover with cold water and cracked or cubed ice. Let stand for 3 hours; drain well. Bring garlic, salt, sugar, mustard seeds, turmeric, vinegar and black pepper to a boil in a pan. Add vegetable mixture and reduce the heat to low. Cook for 5 minutes. Pour into hot sterilized jars, filling jars with the liquid and leaving 1/2 inch headspace. Seal with 2 piece lids. Process in boiling water bath for 10 minutes.
Merlitons (or Mirlitons), are also referred to as chayote squash. Their delicate flavor absorbs the tastes of other foods they are prepared with, making them perfect for seafood casseroles and stuffings. They are used frequently in Creole dishes, as well as in Caribbean and Latin preparations.