Easy and so many variations!! You can also add "mix-in" ingredients like finely chopped crisp bacon, roasted garlic, crumbled blue cheese, hot pepper flakes, & lemon or lime zest. The list goes on and on. Our family devours these and people are always asking us to make them when we invite them over for a cook-out. Try them and you will have the same results!! I guarantee it!! Just like the title says... they melt in your mouth!!
Cut top and root ends off onions and peel skins off. With a sharp paring knife or melon baller, remove the center of the onion, almost to the bottom, about as wide as a quarter. Mince removed onion finely and toss with chopped herbs. Set aside.
Drop a boullion cube into the center of each onion. Press about 2 t. of minced onion mixture down on top of boullion cube. Place 1 drop of liquid smoke in center of each onion. Tightly pack about 1 T. firm, cold butter into each hole.
For more intense flavor, repeat step 2, skipping the liquid smoke addition. Otherwise just add remaining minced onions to onion holes and top with remaining butter. (It is ok if the filling is mounded up above the top of the onion as it will cook down.)Grind pepper over the top of each filled onion.
Wrap each filled onion tightly in HEAVY DUTY aluminum foil. Place on grill as is or in oven on rimmed baking sheet (about 375) for about 45 minutes or until the onion is very soft when squeezed slightly with tongs.
Let onion stand off heat for 5 minutes. CAREFULLY unwrap onions (I unwrap them in a small bowl - there is lots of hot juice that you want to serve them in) and remove from foil. Pour juices over tops of onions and serve immediately.
I have found that combining different boullion is good. I especially like to use tomato (found in the Mexican foods aisle) and beef cubes together. Beef and chicken is good as well. With so many flavorings to chose from, make your own unique taste and enhance it with your fresh herbs.