Yes sir. I use a teaspoon and I heat the plastic in a 4 ounce pyrex cup. Everything comes down to controling how much plastic is in the spoon and having the plastic and mold very close to one another. If you try this, get your things together and practice doing it with junk plastic. It takes some getting used to but if you are using something that could well go in the trash in the first place you're way less likely to give up on it. It does take some practice.
I'd open a small fry or some similar mold and lay it out in front of me then I'd start dipping the plastic into the belly area using a real dark color, maybe black. First try to get the right amount of plastic in the cavities. When you think its right, close the mold and shoot it using using a lighter plastic color. When you open the mold, you want to study the castings, looking for weak spots or where the belly pour may have interfered with the fill shot. On the dud cavities, try to find what caused what, then you'll know when you hand pour again what to look for as far as problems. Its easy to lift a bad pour in the belly cavity then re-pour it when you are making good colors.
The process is super easy but you have to invest the time to get the technique down before you use good plastic or you can get frustrated.
One thing to completely ignore is how the plastic you just poured into the belly section wants to look like a small puddle instead of laying nice and flat like a plate gives you. The lam plate is nice, but the most realisting looking baits will come from cavities that get hand poured and do not have precise straight lines between colors. Remember that nothing in nature is perfect and hand pouring the bellies replicates that as close to perfect as we can get.