Preheat oven to 220C/200C fan. Cook pasta in a saucepan of salted boiling water until al dente. Drain and return to the pan.
For the topping, heat oil in a frying pan over medium-high heat. Add the chopped bacon rashers. Cook, stirring, for 3-4 minutes or until golden. Add 15g of butter and stir until melted. Add the breadcrumbs and cook, tossing, for 3-4 minutes or until lightly golden. Remove from heat. Stir in the thyme.
Grease twelve 125ml (1⁄2 cup) muffin pans with some melted butter and dust lightly with flour. Place in the freezer for 20 minutes to chill. Press the cloves into the shallot. Place the milk, bay leaf, pepper and shallot in a small saucepan. Cook over medium heat until almost boiling. Set aside for 10 minutes to infuse. Strain liquid into a jug. Discard the solids.
Heat the oil in a large saucepan over medium-high heat. Add the smoky bacon and cook, stirring, for 3-4 minutes or until golden. Heat 25g of chopped butter in a second saucepan for 1 minute or until melted. Stir in the flour for 1 minute or until mixture bubbles. Remove from heat. Gradually whisk in the strained milk until smooth. Return to medium heat. Cook, stirring, for 2-3 minutes or until mixture boils and thickens.
Add the cheddar, mustard and cooked smoky bacon to the white sauce and stir until the cheese melts. Season. Add to the pasta and stir until well combined. Stir in the eggs.
Spoon half the pasta mixture into the pans, pressing down with the back of a spoon. Place a mozzarella ball in the centre of each. Top with remaining pasta mixture. Top with the bacon crumb mixture. Bake for 20 minutes or until golden. Allow to cool slightly in pans for 20 minutes.
Run a flat-bladed knife around the edges of the muffins to loosen, then remove. Sprinkle with parsley.