With your Instant Pot set to "Saute," melt the butter in the base. 1 tablespoon unsalted butter
Add in the oats. Stir constantly to ensure they do not burn. Toast until the oats begin to darken slightly and start to smell nutty, about 3 minutes.
1 cup steel cut oats
Pour in the water and stir in the salt.
3 cups water, 1/4 teaspoon salt
Put the lid on and lock it in place. Make sure that the pressure release valve is turned to the sealed position. Turn it off (or hit cancel) and then select High Pressure and 10 minutes for the cook time. (The pressure cooker will take about 9 minutes to come to pressure and then will begin to count down the 10 minutes.)
When the cook time ends, turn off the pressure cooker. Let the pressure release naturally for 5 minutes (in other words, after you turn it off, do nothing for 5 minutes). Then, turn the pressure release valve to venting. When the valve drops, carefully open the lid and stir the oats. They will thicken as they sit.
Serve with fresh fruit, brown sugar, or nuts.