In a largebowlfit for a stand mixer, combine water, eggs, instant yeast, honey, Ketonia bread mix, rye improver, caraway seeds, and butter. Lock into your stand mixer and mix on low speed with paddle attachment for 30 seconds or until just combined. Switch to the bread hook attachment and mix on medium speed for 5 minutes. Once the dough has formed together, dump it onto a clean workspace and knead until smooth. Roll it into a ball and cover for 1hr.

Preheat oven to 400*. After the dough has rested and doubled in size, knead it into the shape you like and set it on a baking sheet lined with parchment paper. Cover and let rest for another hour.

Bake for 30 minutes or internal temperature is 200*. Let cool for 30 minutes before slicing and serving.

Thinly slice 1/4 of an onion and shred your gruyere cheese. Melt 1 tbsp of butter in a small pan and toss in your sliced onions. Cover your onions and simmer over low heat for about 15 minutes, checking every 5 minutes (they shouldn't brown yet). Remove the cover, turn the heat up to medium-high and cook for another 3-5 minutes or until golden brown and caramelized. Transfer to a paper towel to cool.

Preheat yourpanini pressor largeskillet. Slice your Ketonia bread and place 2 slices on a plate. Cover both pieces of bread with 1/4 cup on each and top one slice with caramelized onions. Carefully close your sandwich. Spray your panini press or skillet with nonstick oil and place your sandwich on. Cook for about 5 minutes in a panini press or 3 minutes on each side in a skillet. Cut in half and watch all that cheese ooze!