Preheat oven to 400 degrees. Arrange bacon slices in a single layer on a baking sheet and place in hot oven. Bake until until crisp, 15-20 minutes, checking doneness at 15 minutes to prevent browning. Remove bacon from oven and transfer to paper towel. Reduce oven temperature to 350 degrees.
When the bacon is cool, coarsely chop.
Melt butter in a medium skillet over medium-high heat. Once melted, add chopped shallots, garlic, and Swiss chard stalks to pan. Sauté until translucent (1-2 minutes). Add sliced Swiss chard leaves to skillet and sauté until leaves are wilted. Remove from heat.
In a mixing bowl, whisk eggs, half & half, chopped bacon and Canadian bacon, thyme, pinch of salt and pepper.
Fold in the sautéed vegetables and halved cherry tomatoes into egg mixture.
Pour half of the egg mixture into the unbaked pie crust and add half of the Gruyere cheese.
Pour in remaining egg mixture and top with remaining cheese.
Bake for 35-40 minutes or until crust is golden brown and the center of the quiche is firm. Remove from oven and let rest for 10-15 minutes before serving.