Question on post mean BG number

Hi,
   For last few days I am eating same dinner.  After the dinner:

- Go for 30 minutes walk
- Check for BG# 1 hour
(around 110 - 140)

- Check for BG# 2 hour
(around 160 - 190)

can someone please explain me why am I getting 2nd hour post mean numbers so high?

I have included Avocado in the dinner. Is that a food that may be causing the problem.

Would appreciate your help

Thanks