Heat the water until lukewarm - if you place a finger inside, you should be able to keep it in for a couple of mins until it gets too hot to keep it. Take off heat.
Add the yeast and one teaspoon of the sugar to the water. Let rest for 5-10 minutes or until frothy.
In another bowl, whisk together flour, milk powder, sugar and salt well.
Add the activated yeast mixture and oil .
Mix (by hand or dough hooks) until a shaggy dough forms. You can add more flour (upto a quarter cup) if too wet or little more water if too dry.
Knead this on a floured surface for a couple of minutes until smooth.
Place in a greased bowl , cover and place in a warm are for about an hour or until doubled.
Knock out the air from the risen dough.
Grease a 8 inch square pan with oil / butter.
Press the dough into it spreading it as evenly as possible.
Cover and keep in a warm place for 30 minutes or doubled.
Meanwhile preheat the oven to 180 C / 350 F.
Bake for 28-30 minutes until brown.
Cool completely and slice . I sliced the bread into 4 in one direction and 10 in the other - so got 40 rusks.
Whenever you are ready to bake your rusks, preheat again to 180 C/ 350 F.
Place the sliced rusks close together on a parchment lined or greased baking tray.
Bake for 15 minutes at 180 C / then turn the rusks over and bake again for 15-20 minutes until well browned and hard.
Cool and store in an airtight container
Notes
These can be stored in an airtight container for upto 2 weeks or longer These rusks are lightly sweet , so you can increase or reduce the sugar as per your taste.