Prepare water for pasta and boil according to package directions. Drain and set aside.
Heat a large saucepan or Dutch oven over medium high heat and add bacon. Cook over medium-low heat, stirring occasionally, until bacon is brown and slightly crisp. Remove pan from heat and, using a slotted spoon, transfer cooked bacon to paper towels to drain.
Return pan to heat and add in the garlic and spice pack and sauté for one minute. Whisk in the flour and let it cook for 1-2 minutes, stirring a few times, making sure to not let the garlic burn. Add beer into the pan and whisk out any lumps, scraping the bottom of the pan. Raise heat to medium and let it cook for a minute, then whisk in the milk and sauce pack. Let the mixture come to a heavy simmer and cook for a few minutes until the sauce has slightly thickened.
Turn off the heat, take pan off of the stove top, add in the cheese, and stir until is has melted. Stir in the cooked bacon and cooked pasta. Season to taste with salt and pepper. Serve warm.
For baked macaroni and cheese: Preheat oven to 375 degrees Fahrenheit. Add noodles (once cooked and drained) to a casserole dish, then pour cheese over top, mixing gently to combine. Top with bread crumbs and an additional sprinkle of cheese if desired. Bake for 15-20 minutes or until bubbly and golden on top. Remove from oven and let cool for 5 minutes before serving.