Place the bacon on a wire rack, on top of a cookie sheet, and bake at 350 for 20-30 minutes. Bacon should be cooked thoroughly, but not crispy. You want it flexible. Remove bacon from the oven and let it cool for a few minutes. Then, slice it into ribbons the short way. Don’t discard the bacon grease!!!!
At the same time, cut each tomatoe in half and place them on a baking sheet. Rub the tomatoes with olive oil, salt, and pepper, and place them in the oven with the bacon. After 10 minutes, turn the tomatoes and cook for another 10 minutes. They should be done about the same time as the bacon.
Slice the leek into rounds and put in a colander. Run water over the leek to remove and dirt. Pat dry (or use a salad spinner!). Sauté the leek in butter til it’s translucent.
Cut the Brie into 12 chunks, roughly ½ inch long and ¼ inch thick. (This part isn’t rocket science. No need to get your kid’s ruler out of their backpack). Remove the rind from each piece.
Put one teaspoon of Dijon mustard on each Brie chunk and spread it evenly over the top of the cheese.
Put about ½ slice of bacon on top of the Dijon mustard, and then top with about ¼ tsp of leeks and 2 slices of tomato.
Next, melt the butter in a small saucepan. Add the rendered bacon grease to the butter.
Remove the phyllo from the fridge and lay it on top of a piece of plastic or parchment. Put another piece of plastic or parchment over the top of the phyllo and put a damp towel on top of that. This should keep your phyllo from drying out. With a pastry brush, liberally brush some butter/bacon grease mixture over the bottom of a baking sheet. Lay one sheet of phyllo on the down and brush it with butter/bacon grease. (Make sure you’ve re-covered the remaining phyllo with the parchment and towel). Fold the sheet of phyllo the long way and brush with butter again.
Put about ½ slice of bacon ribbons about 2 inches up from the bottom of the phyllo. Top that with one of the dressed cheese chunks. Now fold the bottom of the phyllo up over the entire thing and roll it all the way up to the other end. Tuck the ends under and put the bundle seam side down. Brush the top with butter.
Repeat the process for the remaining 11 bundles. Don’t worry if a piece of phyllo rips or isn’t exactly flush with the other sheets. Phyllo is delicate, but it’s also very forgiving, as long as you use a lot of butter.
Place the bundlers in the oven (that you’ve kept on this entire time) for 10-15 minutes, or until the tops of the bundles are beautifully browned.