Preheat oven to 400F.
Arrange bacon slices in a single layer on a non-stick or foil-lined baking sheet and bake for 15 to 18 minutes, or until crisp, checking in around the 10-minute mark to ensure bacon isn’t burning. Transfer cooked bacon to paper towel lined plate to soak up excess grease than coarsely chop and set aside.
Melt butter in a medium skillet over medium-high heat then add shallots, garlic, and a pinch of salt and sauté until translucent, about 3 to 5 minutes. Add Swiss chard and sauté until wilted, about 1 to 2 minutes, then remove from heat and let cool.
In a large mixing bowl whisk together eggs, half and half, and salt and pepper then fold in chopped bacon, Canadian bacon, thyme, sauteed Swiss chard mixture, and cherry tomatoes. Pour half of the egg mixture into the frozen pie crust and top with half of the Gruyere cheese. Pour in remaining egg mixture and top with remaining Gruyere cheese then bake for 35 to 40 minutes or until crust is golden brown and the center of the quiche is firm. Remove from oven and let rest for 10 to 15 minutes before serving.