In a small saucepan, gently heat the heavy cream and cinnamon sticks over medium-low heat until steaming. Remove from heat, cover, and let steep for 30 minutes. Discard the cinnamon sticks and let the cream cool.

Preheat your oven to 400°F (200°C). Unroll the tart crust and press it into a 9-inch tart pan. Prick the bottom with a fork, line with parchment paper, and fill with pie weights. Blind bake for 10 minutes, then remove the weights and bake for 5 more minutes. Set aside.

In a skillet over medium heat, cook the chopped beef bacon until crispy. Remove with a slotted spoon and drain on paper towels, leaving the drippings in the pan.

Add the butter and diced shallot to the skillet. Sauté for 2 minutes until softened. Add the cleaned morel mushrooms and cook for 5 to 7 minutes until tender and browned. Remove from heat.

In a medium mixing bowl, whisk together the eggs and the cooled cinnamon-infused cream. Stir in the grated Gruyere cheese, cooked beef bacon, sautéed morel mushrooms, salt, and black pepper.

Pour the creamy filling evenly into the pre-baked tart crust.

Bake at 375°F (190°C) for 20 to 25 minutes, or until the filling is set and the top is lightly golden. Let cool for 10 minutes before slicing and serving.