Open a crafting table
Place 5 iron ingots in the top row and middle-left, middle-right, and bottom-left, bottom-right slots
Place 1 furnace in the center slot
Place 3 smooth stone in the bottom row
Take the blast furnace from the result slot
Open a crafting table
Place 5 iron ingots in the top row and middle-left, middle-right, and bottom-left, bottom-right slots
Place 1 furnace in the center slot
Place 3 smooth stone in the bottom row
Take the blast furnace from the result slot