- Set your oven to broil. Place an oven rack in the upper third portion of the oven. 
- Line a sheet pan with parchment paper or aluminum foil. Lay out the six slices of bread on the pan. 
- Melt the butter in the microwave. Use a pastry brush to apply a light coating of melted butter on one side of each slice of bread. 
- Toast bread on both sides (about 2 minutes per side, watch closely so as not to burn) until both sides are toasted. One side of each slice of bread will be buttered and one side will not. 
- In a small bowl, mix together the mayonnaise with tarragon, garlic powder, lemon juice, salt and pepper. 
- For each sandwich, spread the first slice of bread (on the buttered side) with a thin layer of mayonnaise. Make sure to go all the way to the edges. 
- Layer on three slices of ham (for each sandwich). 
- Top with two slices of cheddar cheese (for each sandwich). 
- Top with two lettuce leaves (for each sandwich). 
- Spread a thin layer of the mayonnaise on BOTH sides of the middle slice of bread and place it on top of the lettuce. 
- Then top that second slice of bread with three slices of chicken (or turkey). 
- Top the chicken with one or two tomato slices and three slices of bacon. 
- Spread the remaining mayonnaise onto the final piece of bread (on the buttered side).  
- Place the final piece of bread on top of the bacon (for each sandwich). 
- Use a sharp knife to slice each sandwich into equal quarters. 
- Secure each triangle with a frilled toothpick. Serve immediately.