First grease some steel plate with oil or butter. You can use greased butter paper or parchment paper too. Keep aside.
Add sugar in a non stick pan and start stirring on low heat.
After couple of minutes, sugar will melt and turn brown.
Add butter and mix.
Add cashews and almonds.
Stir so that everything mixes well.
IMMEDIATELY transfer the mixture into a greased steel plate.
Spread the mixture evenly into the plate before the mixture turns cool.
Let it cool down completely.
Pick up the plate and push it upwards from the bottom so that caramelized sugar mixture (praline) can be separated from the bottom. (Refer video for easy understanding.)
Break the praline into small pieces and add them to a blender.
Grind them to a coarse powder. Keep aside.
MAKING OF BUTTERSCOTCH COOKIES
Take a bowl and add butter and sugar.
Whisk them to creamy mixture using electric beater. However you can use wire whisk also. In 2 to 3 minutes (with electric beater), butter will turn creamy.
Now add wheat flour, baking soda, butterscotch essence and salt. Skip salt if the butter you are using is already salted.
Mix everything well.
Time to add the coarsely powdered praline and mix.
Add yellow food colour. However it is purely optional. Mix.
Now add a very little milk at a time and by using your hand, start bringing everything together. Remember, in making a dough, only bring the mixture together and don't knead it.
A normal dough is ready.
Make small lemon size pieces of the dough. We could made 19 pieces.
Now roll each piece into a ball by rolling them between your palms one by one.
Slightly flatten the balls with your fingers.
Arrange all balls on a baking tray lined with greased butter paper or parchment paper. See, keep distance in each ball as they will spread a little on baking.
Place the tray in refrigerator for 30 minutes.
After the said period, bake @160°C in a preheated oven in the middle rack with both the rods on for 25 to 30 minutes.
Once done, take the tray out and let Cookies cool down completely.
Butterscotch cookies are ready.
Notes
If you have readymade Butterscotch chips, then skip the whole process of making praline. Just add 1/4 cup of Butterscotch chips while preparing Cookies dough.