Bring a pot of salted water to a boil over high heat. Cook pasta til al dente. Drain pasta, run it under cold water and return to pot.
Cook bacon in skillet over medium high heat for 5 to 7 minutes or to crisp. Remove bacon from pan with slotted spoon and drain on paper towels. Brush maple syrup on the drained bacon. When cool, crumble bacon and set aside.
Heat butter in pan over medium low heat. Stir in flour the thyme and cook,stirring constantly for a minute or til mixture turns slightly beige is bubbly and appears to have grown in volume. Increase heat to medium and slowly whisk in the cream. Bring to a boil, whisking frequently. Reduce heat to low, simmer for 2 minutes. Add cheese to sauce by 1/2 cup measures, stirring til it melts before making another addition. Stir in lemon juice and nutmeg
Add saucej to pasta, stir in bacon and season to taste with salt and pepper. Cook over low heat til pasta is hot and coated with sauce. Serve at once, garnishing each serving with apple. Note; The sauce can be made up to 2 days ahead and refrigerated. Bring to a simmer over low heat. Don't cook the pasta until just before serving.