Combine the flour and oil

• Put the flour and oil in a heavy-bottomed pot or cast iron skillet.
• Stir with a spoon until completely mixed, before turning on the heat.

Cook the roux on medium heat

• Place the pot over medium heat.
• Stir constantly without stopping, scraping the edges of the pot with a spatula.
• Keep stirring patiently and never take your eyes off it, as it can burn quickly.

Watch the color develop

• The roux first turns a peanut butter color, good for an etouffee.
• It then reaches the color of milk chocolate, but this is still not dark enough.
• Keep going until it is very dark, like dark chocolate.

Take off the heat and cool

• Remove the pot from the heat once the roux is dark enough.
• Keep stirring with the spoon; the residual heat will cook it a little further.
• Let it cool completely to room temperature, during which it will darken more.

Remove the excess oil

• Pour off the oil that rises to the top.
• Lay a paper towel on the surface to soak up any remaining oil.

Store the roux

• Transfer any leftover roux to a mason jar.
• Keep it in the fridge for a couple of months, or in the freezer for a long time.