Render the Bacon:
Cut bacon in half and fry in a small pan over medium heat until evenly crisp. Set aside and reserve the bacon fat.

Caramelize the Onions:
In the same pan or separate skillet, sauté sliced onions in olive oil or bacon fat over medium-low heat.
Add a splash of water and cover early to steam.
Cook 30–45 mins, stirring occasionally until soft, jammy, and golden. Season with salt and thyme.

Make the Aioli:
Mash roasted garlic cloves into a bowl.
Add mayo, chopped rosemary, lemon juice, salt, and pepper. Mix until smooth and creamy.

Toast the Bread:
In a cast iron pan, toast both sides of your bread slices using a thin layer of reserved bacon grease until golden and crisp.

Fry the Eggs:
In bacon fat or clean pan, fry 2 eggs over medium-high heat. Season with salt and pepper.
Cook until whites are set and yolks are still runny (or to your preferred doneness).

Prep Veg:
Lightly salt your tomato slices.
Toss arugula with lemon juice, olive oil, and salt.

Assemble the Sandwich:
Spread aioli on both slices of toasted bread.
Layer caramelized onions, bacon, tomato slices, fried eggs, and havarti cheese.
Melt the cheese briefly under the broiler (optional).
Top with lemon-dressed arugula and close the sandwich.

Serve:
Slice and serve warm — ideally with a strong coffee and a weekend morning playlist.