If using fresh corn ears, carefully remove the kernels (butil ng mais) using fork tines (gamitin ang tinidor). Insert the fork between kernels and gently pry them off, keeping them whole to maintain the traditional texture. Never use a knife as this will damage the kernels' texture.
Place the corn kernels in a large pot (ilagay ang mga butil ng mais sa kaldero) and add enough water to cover them completely (lagyan ng tubig). Bring to a gentle boil over medium heat (pakuluan sa katamtamang init) - you should see small bubbles, not a violent boil.
Reduce heat to low, cover the pot, and simmer for 15-20 minutes (pahinaan ang apoy at takpan) until the kernels are tender but still hold their shape. Test a kernel for doneness - it should be chewy but not mushy. Drain thoroughly in a colander (salain ng mabuti).
While the corn cooks, prepare fresh coconut (niyog) if using a whole one. Grate it just before serving for the best flavor and texture. Have your margarine or butter (mantikilya) ready at room temperature for easy spreading.
Portion the warm corn into serving bowls. Top generously with freshly grated coconut, add your desired amount of margarine, and finish with a sprinkle of salt (asin) or sugar (asukal) according to preference.
Serve immediately while still warm, traditionally between 3-5 PM for merienda time. Offer both salt and sugar on the side so everyone can adjust to taste.