How did we do it? 3 ways!
1) Milo Kor-song (hot chocolate drink)
We started off with giving her some time to get used to the texture by treating it first as 'soft' food - dipping it in diluted Milo Kor-song! (Without added sugar)
2) Mix of white and brown
When I first added added it to her bento box, we used a mix of white and brown in the first week: that is when I made mini sandwiches, white bread goes on top while the brown bread will be the bottom slice
3) Butter / margarine
The last trick was that I added a bit of butter / margarine so that the texture is smoother and the bread, less dry :) (If your kiddos like veggies in their sandwiches, you can add that too as that gives the bread moisture)
And of course, having fun designs like these help (her mystery bento boxes are apparently a topic amongst her friends in her daily Chinese class)