In a medium saucepan, combine oats, 1 1/2 cups water, butter and salt . Bring to a boil, reduce heat, and simmer 15 minutes, stirring occasionally until oats are softened. Allow mixture to cool.
Meanwhile, in the large bowl of a standing mixer, dissolve yeast in 1/4 cup warm water and set aside until doubled in volume, about 10 minutes. Once oats have cooled to 115ºF (about the same temperature as the water the yeast was dissolved in) add to the yeast mixture and combine on low speed of mixer. Add molasses and final 1/2 cup of warm water, and beat to combine.
Gradually add the flour until dough comes together but is still moist. Attach dough hook to mixer and knead for about 10 minutes on low to medium speed until dough forms a smooth, elastic ball. (You may alternatively knead dough by hand for 10-15 minutes). Place dough in an oiled bowl, turning once to coat dough with oil; cover with plastic wrap and allow to rise for 1 hour, or until doubled in bulk.
Punch down dough and divide into two equal portions. Shape each portion into a ball and let rest 30 minutes. Shape into loaves and place in loaf pans, or make 2 free-standing round loaves placed seam-side down on parchment-lined baking sheet. Cover with plastic wrap and let rise 1 hour until doubled in volume.
Preheat oven to 375ºF (190ºC). Use a knife or scissors to make slashes in round loaves. Bake in centre of oven for 35-45 minutes until bottom sounds hollow when tapped. Cool on wire racks.