Espresso and Lime

0 Preheat your oven to 425 degrees 
1 Slice the onions in half, remove the peel and trim back the base to clean it up, but leave enough to hold the onion halves together 
2 Place the onions cut side down into an oven safe skillet and set aside for now
3 Place 2 cups of beef broth into a small sauce over medium high heat and bring to a boil 
4 As soon as the broth is boiling, remove from the heat and whisk in 4 tablespoons of butter, 1 tablespoon of soy sauce, 1 tablespoon of tomato paste and 1 teaspoon of worcestershire sauce until everything is fully combined 
5 Place the onions into the broth cut side down and cover the skillet with foil
6 Bake the onions covered for 30 minutes in a 425 degree oven and then carefully transfer the skillet out onto a heatproof surface 
7 Remove the foil and carefully flip the onions cut side up
8 Spoon the sauce over the onions and place them back into a 425 degree oven
9 Bake uncovered for another 40 minutes basting the onions every 10 minutes 
10 Serve with crusty bread and garnish with finely shredded Gruyère and fresh thyme