Layer the torn croissants evenly in a baking dish
Sprinkle the ham, gruyere, and havarti chunks throughout so you get little melty surprises in every bite
In a separate bowl, whisk together the eggs, heavy cream, Dijon mustard, garlic, salt, pepper, and thyme until smooth
Pour the mixture evenly over the croissants, gently pressing down so everything soaks in
Cover with foil and bake at 350°F for 30–45 minutes until set
Remove the cover and broil for 2–3 minutes until golden and bubbly
Finish with fresh chives if using
Optional: dust lightly with powdered sugar and serve with raspberry jam on the side
