Meanwhile, prepare the prosciutto bacon: Preheat oven to 375 degrees. Place prosciutto on a baking rack set in a baking sheet. This allows the prosciutto to not cook in it's grease. Feel free to bake directly on baking sheet, but know that it will be greasier.
Bake prosciutto until crispy, about 15 minutes. With closely to ensure it doesn't burn.
While prosciutto bacon is cooking, prep other ingredients. Wash, dry, and chop lettuces. Chop red onion, cherry tomatoes, slice peppercini, as well as hard-boiled egg. Cube or grate Grana Padano.
Make the vinaigrette: combine all ingredients besides olive oil in a small bowl. Whisk to combine, slowly drizzling in olive oil. Season with salt and pepper.
To assemble the salad, mix romaine and green leaf lettuces together and place on plate. Cube cooled chicken and crumble prosciutto bacon. Arrange ingredients in vertical rows on top of greens: chicken, bacon, hard boiled egg, artichokes, tomato, red onion, pepperocini, and Grana Padano. Top with olives, and drizzle with dressing.
Enjoy!