Grilled cheese on toast is a big hit! I used wholemeal bread, toast it, then I get a potato peeler and 'peel' some full fat cheese and put on the toast, then I grill it under the griller. Cut into strips so they can hold it and eat. Using the peeler for cheese just means you are not putting it on too thick. I also spread some avocado on first too, then cheese and grill. Fruit puree's are another good one on toast or cream cheese.
You would need to check with the guidelines in your country regarding when to give egg white. I have given from 9months and L is ok with that (make sure it's really cooked), but each country is different.
hth