To solve the expression \( \frac{23}{20} - \frac{40}{10} + \frac{1}{12} \div \frac{-5}{6} \), we need to follow the order of operations (PEMDAS/BODMAS):

1. **Parentheses/Brackets**
2. **Exponents/Orders**
3. **Multiplication and Division (from left to right)**
4. **Addition and Subtraction (from left to right)**

Let's break it down step by step:

### Step 1: Division
First, we handle the division part of the expression \( \frac{1}{12} \div \frac{-5}{6} \).

Dividing by a fraction is the same as multiplying by its reciprocal:
\[ \frac{1}{12} \div \frac{-5}{6} = \frac{1}{12} \times \frac{6}{-5} = \frac{1 \times 6}{12 \times -5} = \frac{6}{-60} = \frac{-1}{10} \]

So the expression now becomes:
\[ \frac{23}{20} - \frac{40}{10} + \frac{-1}{10} \]

### Step 2: Simplify Fractions
Next, simplify the fractions where possible:
\[ \frac{40}{10} = 4 \]

So the expression now is:
\[ \frac{23}{20} - 4 + \frac{-1}{10} \]

### Step 3: Common Denominator
To combine the fractions, we need a common denominator. The least common multiple of 20 and 10 is 20.

Convert \(\frac{-1}{10}\) to a fraction with a denominator of 20:
\[ \frac{-1}{10} = \frac{-1 \times 2}{10 \times 2} = \frac{-2}{20} \]

Now the expression is:
\[ \frac{23}{20} - 4 + \frac{-2}{20} \]

Combine the fractions:
\[ \frac{23}{20} + \frac{-2}{20} = \frac{23 - 2}{20} = \frac{21}{20} \]

So the expression now is:
\[ \frac{21}{20} - 4 \]

### Step 4: Subtract
Convert 4 to a fraction with a denominator of 20:
\[ 4 = \frac{4 \times 20}{1 \times 20} = \frac{80}{20} \]

Now subtract the fractions:
\[ \frac{21}{20} - \frac{80}{20} = \frac{21 - 80}{20} = \frac{-59}{20} \]

So, the final result is:
\[ \frac{-59}{20} \]

Or as a mixed number:
\[ -2 \frac{19}{20} \]

Thus, the simplified result of the expression \( \frac{23}{20} - \frac{40}{10} + \frac{1}{12} \div \frac{-5}{6} \) is \( \frac{-59}{20} \) or \( -2 \frac{19}{20} \).