Heat your water to exactly 98°F/37°C (maligamgam na tubig). In a large mixing bowl, combine the warm water with 1½ teaspoons sugar. Sprinkle 4 teaspoons of active dry yeast over the mixture and allow it to stand for 10 minutes until it becomes bubbly and foamy (maghintay hanggang lumitaw ang mga bula).
Stir 1 cup of all-purpose flour into the yeast mixture until smooth (haluing mabuti hanggang maging makinis). Cover this starter dough with a damp cloth (basang tela) and let it rise in a warm place at 85°F/29°C for 30 minutes. This is your starter dough, also known as "paunang masa."
While waiting for your starter dough, in a separate large bowl, cream together ⅛ cup softened butter and ¾ cup sugar until light and fluffy (paghaluin ang mantikilya at asukal hanggang lumambot at pumuti). Add 5 egg yolks one at a time, beating well after each addition (isang dilaw ng itlog kada paghuhulog). Mix in 1 cup of fresh milk gradually (unti-unting ilagay ang gatas).
Begin adding the remaining 4 cups of flour to your butter mixture gradually, mixing well after each addition (unti-unting ilagay ang harina). Once all flour is incorporated, add your risen starter dough to this mixture. Using a stand mixer with a dough hook attachment or your hands, knead the dough for 15 minutes until it becomes smooth and elastic (masahin hanggang maging makinis at umaabot).
Place your kneaded dough in a large greased bowl (minamantikilyang mangkok). Cover with a damp cloth and let it rise in a warm place at 85°F/29°C for 2 hours or until doubled in size (patababin sa loob ng dalawang oras).
After the first rise, punch down the dough and divide it into 24 equal portions (hatiin sa 24 na pantay na piraso). Take each portion and roll it out into a 12×6 inch rectangle using a rolling pin (bilutan hanggang maging parihaba). Brush each rectangle with melted butter (pahiran ng tinunaw na mantikilya).
Starting from the long edge, roll each rectangle tightly like a jelly roll (irolyo ng mahigpit tulad ng jelly roll). Form each rolled piece into a spiral shape, tucking the end underneath (irolyo sa hugis ng suso ng susong pilipit). Place each spiral in a greased ensaymada mold or muffin tin.
Cover your shaped ensaymadas with a damp cloth and let them rise again at 85°F/29°C for 2 hours or until doubled in size. Near the end of this rising time, preheat your oven to 375°F/190°C.
Bake the ensaymadas for 12-15 minutes until golden brown. Watch them carefully as they can brown quickly. Immediately after removing from the oven, brush the hot ensaymadas generously with melted butter (pahiran agad ng tinunaw na mantikilya).
While still warm, top each ensaymada with a generous amount of grated cheese and sprinkle with sugar (lagyan ng maraming keso at asukal). Let them cool slightly before serving, about 5-10 minutes.
For storage (paraan ng pagtatago), keep at room temperature in an airtight container for up to 2 days. They can be refrigerated for up to a week or frozen for up to 3 months. To reheat, warm in a preheated 350°F/175°C oven for 5 minutes or microwave individual pieces for 15-20 seconds.
For best results, serve warm with hot chocolate or strong coffee. Ensaymada is traditionally enjoyed as a merienda (afternoon snack) between 3-4 PM, but it makes a wonderful breakfast or dessert any time of day.