Cook the bacon until it is crispy. Once it is cool, crumble into pieces. In a large stock pot, cook the pasta until al dente. (Add salt to the water when you are boiling the pasta). Drain the pasta. Put the pasta in a large bowl and add the milk. Toss to combine.
Cut the cherry tomatoes in half and add to the bowl. Add the grated garlic cloves, salt, thyme, chives and ¾ of the bacon. Lightly toss to combine all the ingredients. Add the mayonnaise and sour cream and stir until all the pasta is coated. Stir in the lettuce and top with the remaining bacon.