Chop the peanuts into smaller pieces, or run them in the mixer/ blender to break them. Do not make them into smaller crumbs or a powder. Keep aside.
Run the oats as well and grind into a coarse powder. Keep aside.
In a bowl, sift together the all purpose and whole wheat flours, salt and baking powder. Add the powdered oats and peanut pieces and mix well. Keep aside.
In another bowl, beat the butter and sugar till creamy. Add the oil and beat till well mixed. Now add the egg and vanilla extract and beat together till mixed. Add the dry ingredients from the other bowl and mix well, using a wooden spoon till well blended.
Divide into balls roughly the size of big walnuts/ small lemons and lightly flatten, placing them on a baking sheet leaving enough space between them. Press about 6 each of the Gems/ Smarties/ MMs on the top of each cookie. This may seem a lot, but the cookies will spread a bit while baking and will look okay.
Bake at 190C for between 12 and 15 minutes till the cookies start browning lightly around the edges. Remove from the oven and cool on the sheet for about 5 minutes. The cookies will be very soft and need these 5 minutes to harden. Remove and place on a rack to cool completely.
Serve or store in air-tight containers. This recipe makes about 2 dozen cookies depending on the size. I got 20 cookies which were approx. 2 3/4" in diameter each.
If you prefer, you can top the cookies with white or dark chocolate chips instead. They taste just as good. These cookies are a great after school snack for children and I know that many adults would also find it hard to resist them.