Whisk one ¼-oz. envelope active dry yeast, 2 tsp. honey, and 2½ cups room temperature water in a medium bowl and let sit 5 minutes.
Add 5 cups all-purpose flour and 5 tsp. sea salt and mix with a rubber spatula until a dough forms and no dry marks remain.
Drizzle 4 Tbsp. extra-virgin olive oil into a big bowl that will fit in your refrigerator. Transfer dough to bowl and turn to coat it in oil. Cover with a silicone lid or plastic wrap and chill until dough is doubled in size. The dough should look very bubbly and alive. Let rise for at least 8 hours or up to 1 day. If you're in a hurry, you can also let it rise at room temperature until doubled in size, 3–4 hours.
Generously butter a 13x9" baking pan, for thicker focaccia that is great for sandwiches, or an 18x13" rimmed baking sheet, for focaccia that's thinner, crispier, and great for snacking. Pour 1 Tbsp. extra-virgin olive oil into center of pan. Keep dough in the bowl and using a fork in each hand, gather up edges of dough farthest from you and lift up and over into center of bowl. Give the bowl a quarter turn and repeat process. Do this two more times. Your goal is to deflate dough while you form it into a rough ball. Transfer dough to your buttered pan. Pour any oil left in bowl over and turn dough to coat it in oil. Let rise, uncovered, in a dry, warm spot (like near a radiator or on top of the fridge or a preheating oven) until doubled in size, or for about 2 hours.
Place a rack in middle of your oven; preheat to 450°. To see if the dough is ready, poke it with your finger and it should spring back slowly, leaving a small visible indentation. If it springs back quickly, the dough isn’t ready and needs more time. Lightly oil your hands. Gently stretch out dough to fill your pan. Dimple focaccia all over with your fingers, creating very deep depressions in the dough (reach your fingers all the way to the bottom of the pan).