Preheat the oven to 180 degrees Celsius (356 F). Select standard program (don't select Turbo; it will dry out the almonds)
Spread the almonds evenly on a wide baking tray.
Toast the almonds for 4-5 minutes for whole almonds, 3-5 minutes for halved almonds - Toast just until the almonds start to turn golden - do not let them turn golden - so that they do not dry out.
Cool for about 5 minutes and transfer to a strong blender while the almonds are still warm. Process for 5-10 minutes until you get a smooth mixture (depending on the power of the blender). Occasionally stop the blender and scrape the sides with a spatula.
After about five minutes add the the oil and process for about a minute until the mixture turns into butter . Add more almond oil if necessary.
Transfer to a jar and keep in the refrigerator.